1
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Koenig AB, Tan A, Abdelaal H, Monge F, Younossi ZM, Goodman ZD. Review article: Hepatic steatosis and its associations with acute and chronic liver diseases. Aliment Pharmacol Ther 2024; 60:167-200. [PMID: 38845486 DOI: 10.1111/apt.18059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2024] [Revised: 04/23/2024] [Accepted: 05/13/2024] [Indexed: 06/28/2024]
Abstract
BACKGROUND Hepatic steatosis is a common finding in liver histopathology and the hallmark of metabolic dysfunction-associated steatotic liver disease (MASLD), formerly known as non-alcoholic fatty liver disease (NAFLD), whose global prevalence is rising. AIMS To review the histopathology of hepatic steatosis and its mechanisms of development and to identify common and rare disease associations. METHODS We reviewed literature on the basic science of lipid droplet (LD) biology and clinical research on acute and chronic liver diseases associated with hepatic steatosis using the PubMed database. RESULTS A variety of genetic and environmental factors contribute to the development of chronic hepatic steatosis or steatotic liver disease, which typically appears macrovesicular. Microvesicular steatosis is associated with acute mitochondrial dysfunction and liver failure. Fat metabolic processes in hepatocytes whose dysregulation leads to the development of steatosis include secretion of lipoprotein particles, uptake of remnant lipoprotein particles or free fatty acids from blood, de novo lipogenesis, oxidation of fatty acids, lipolysis and lipophagy. Hepatic insulin resistance is a key feature of MASLD. Seipin is a polyfunctional protein that facilitates LD biogenesis. Assembly of hepatitis C virus takes place on LD surfaces. LDs make important, functional contact with the endoplasmic reticulum and other organelles. CONCLUSIONS Diverse liver pathologies are associated with hepatic steatosis, with MASLD being the most important contributor. The biogenesis and dynamics of LDs in hepatocytes are complex and warrant further investigation. Organellar interfaces permit co-regulation of lipid metabolism to match generation of potentially toxic lipid species with their LD depot storage.
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Affiliation(s)
- Aaron B Koenig
- Beatty Liver and Obesity Research Program, Inova Health System, Falls Church, Virginia, USA
| | - Albert Tan
- Beatty Liver and Obesity Research Program, Inova Health System, Falls Church, Virginia, USA
- Center for Liver Diseases, Inova Fairfax Hospital, Falls Church, Virginia, USA
| | - Hala Abdelaal
- Beatty Liver and Obesity Research Program, Inova Health System, Falls Church, Virginia, USA
- Center for Liver Diseases, Inova Fairfax Hospital, Falls Church, Virginia, USA
| | - Fanny Monge
- Beatty Liver and Obesity Research Program, Inova Health System, Falls Church, Virginia, USA
- Center for Liver Diseases, Inova Fairfax Hospital, Falls Church, Virginia, USA
| | - Zobair M Younossi
- Beatty Liver and Obesity Research Program, Inova Health System, Falls Church, Virginia, USA
- The Global NASH Council, Center for Outcomes Research in Liver Diseases, Washington, DC, USA
| | - Zachary D Goodman
- Beatty Liver and Obesity Research Program, Inova Health System, Falls Church, Virginia, USA
- Center for Liver Diseases, Inova Fairfax Hospital, Falls Church, Virginia, USA
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2
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Sapia J, Vanni S. Molecular dynamics simulations of intracellular lipid droplets: a new tool in the toolbox. FEBS Lett 2024; 598:1143-1153. [PMID: 38627196 DOI: 10.1002/1873-3468.14879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Revised: 03/14/2024] [Accepted: 03/25/2024] [Indexed: 05/25/2024]
Abstract
Lipid droplets (LDs) are ubiquitous intracellular organelles with a central role in multiple lipid metabolic pathways. However, identifying correlations between their structural properties and their biological activity has proved challenging, owing to their unique physicochemical properties as compared with other cellular membranes. In recent years, molecular dynamics (MD) simulations, a computational methodology allowing the accurate description of molecular assemblies down to their individual components, have been demonstrated to be a useful and powerful approach for studying LD structural and dynamical properties. In this short review, we attempt to highlight, as comprehensively as possible, how MD simulations have contributed to our current understanding of multiple molecular mechanisms involved in LD biology.
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Affiliation(s)
- Jennifer Sapia
- Department of Biology, University of Fribourg, Fribourg, Switzerland
| | - Stefano Vanni
- Department of Biology, University of Fribourg, Fribourg, Switzerland
- Université Côte d'Azur, Inserm, CNRS, Institut de Pharmacologie Moléculaire et Cellulaire, Valbonne, France
- Swiss National Center for Competence in Research (NCCR) Bio-inspired Materials, University of Fribourg, Fribourg, Switzerland
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3
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Griseti E, Bello AA, Bieth E, Sabbagh B, Iacovoni JS, Bigay J, Laurell H, Čopič A. Molecular mechanisms of perilipin protein function in lipid droplet metabolism. FEBS Lett 2024; 598:1170-1198. [PMID: 38140813 DOI: 10.1002/1873-3468.14792] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2023] [Revised: 11/27/2023] [Accepted: 12/11/2023] [Indexed: 12/24/2023]
Abstract
Perilipins are abundant lipid droplet (LD) proteins present in all metazoans and also in Amoebozoa and fungi. Humans express five perilipins, which share a similar domain organization: an amino-terminal PAT domain and an 11-mer repeat region, which can fold into amphipathic helices that interact with LDs, followed by a structured carboxy-terminal domain. Variations of this organization that arose during vertebrate evolution allow for functional specialization between perilipins in relation to the metabolic needs of different tissues. We discuss how different features of perilipins influence their interaction with LDs and their cellular targeting. PLIN1 and PLIN5 play a direct role in lipolysis by regulating the recruitment of lipases to LDs and LD interaction with mitochondria. Other perilipins, particularly PLIN2, appear to protect LDs from lipolysis, but the molecular mechanism is not clear. PLIN4 stands out with its long repetitive region, whereas PLIN3 is most widely expressed and is used as a nascent LD marker. Finally, we discuss the genetic variability in perilipins in connection with metabolic disease, prominent for PLIN1 and PLIN4, underlying the importance of understanding the molecular function of perilipins.
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Affiliation(s)
- Elena Griseti
- Institut des Maladies Métaboliques et Cardiovasculaires - I2MC, Université de Toulouse, Inserm, Université Toulouse III - Paul Sabatier (UPS), France
| | - Abdoul Akim Bello
- Institut de Pharmacologie Moléculaire et Cellulaire - IPMC, Université Côte d'Azur, CNRS, Valbonne, France
| | - Eric Bieth
- Institut des Maladies Métaboliques et Cardiovasculaires - I2MC, Université de Toulouse, Inserm, Université Toulouse III - Paul Sabatier (UPS), France
- Departement de Génétique Médicale, Centre Hospitalier Universitaire de Toulouse, France
| | - Bayane Sabbagh
- Centre de Recherche en Biologie Cellulaire de Montpellier - CRBM, Université de Montpellier, CNRS, France
| | - Jason S Iacovoni
- Institut des Maladies Métaboliques et Cardiovasculaires - I2MC, Université de Toulouse, Inserm, Université Toulouse III - Paul Sabatier (UPS), France
| | - Joëlle Bigay
- Institut de Pharmacologie Moléculaire et Cellulaire - IPMC, Université Côte d'Azur, CNRS, Valbonne, France
| | - Henrik Laurell
- Institut des Maladies Métaboliques et Cardiovasculaires - I2MC, Université de Toulouse, Inserm, Université Toulouse III - Paul Sabatier (UPS), France
| | - Alenka Čopič
- Centre de Recherche en Biologie Cellulaire de Montpellier - CRBM, Université de Montpellier, CNRS, France
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4
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Maestri A, Garagnani P, Pedrelli M, Hagberg CE, Parini P, Ehrenborg E. Lipid droplets, autophagy, and ageing: A cell-specific tale. Ageing Res Rev 2024; 94:102194. [PMID: 38218464 DOI: 10.1016/j.arr.2024.102194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2023] [Revised: 12/22/2023] [Accepted: 01/08/2024] [Indexed: 01/15/2024]
Abstract
Lipid droplets are the essential organelle for storing lipids in a cell. Within the variety of the human body, different cells store, utilize and release lipids in different ways, depending on their intrinsic function. However, these differences are not well characterized and, especially in the context of ageing, represent a key factor for cardiometabolic diseases. Whole body lipid homeostasis is a central interest in the field of cardiometabolic diseases. In this review we characterize lipid droplets and their utilization via autophagy and describe their diverse fate in three cells types central in cardiometabolic dysfunctions: adipocytes, hepatocytes, and macrophages.
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Affiliation(s)
- Alice Maestri
- Division of Cardiovascular Medicine, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden; Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Paolo Garagnani
- Department of Medical and Surgical Sciences (DIMEC), University of Bologna, Bologna, Italy; IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy
| | - Matteo Pedrelli
- Cardio Metabolic Unit, Department of Laboratory Medicine, and Department of Medicine (Huddinge), Karolinska Institutet, Stockholm, Sweden; Medicine Unit of Endocrinology, Theme Inflammation and Ageing, Karolinska University Hospital, Stockholm, Sweden
| | - Carolina E Hagberg
- Division of Cardiovascular Medicine, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden; Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Paolo Parini
- Cardio Metabolic Unit, Department of Laboratory Medicine, and Department of Medicine (Huddinge), Karolinska Institutet, Stockholm, Sweden; Medicine Unit of Endocrinology, Theme Inflammation and Ageing, Karolinska University Hospital, Stockholm, Sweden
| | - Ewa Ehrenborg
- Division of Cardiovascular Medicine, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden; Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden.
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5
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Kazemisabet F, Bahrami A, Ghosh R, Różycki B, Bahrami AH. Molecular mechanisms and energetics of lipid droplet formation and directional budding. SOFT MATTER 2024; 20:909-922. [PMID: 38189157 DOI: 10.1039/d3sm01438j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
The formation and budding of lipid droplets (LDs) are known to be governed by the LD size and by membrane tensions in the endoplasmic reticulum (ER) bilayer and LD-monolayers. Using coarse-grained simulations of an LD model, we first show that ER-embedded LDs of different sizes can form through a continuous transition from wide LD lenses to spherical LDs at a fixed LD size. The ER tendency to relax its bilayer modulates the transition via a subtle interplay between the ER and LD lipid densities. By calculating the energetic landscape of the LD transition, we demonstrate that this size-independent transition is regulated by the mechanical force balance of ER and LD-tensions, independent from membrane bending and line tension whose energetic contributions are negligible according to our calculations. Our findings explain experimental observation of stable LDs of various shapes. We then propose a novel mechanism for directional LD budding where the required membrane asymmetry is provided by the exchange of lipids between the LD-monolayers. Remarkably, we demonstrate that this budding process is energetically neutral. Consequently, LD budding can proceed by a modest energy input from proteins or other driving agents. We obtain equal lipid densities and membrane tensions in LD-monolayers throughout budding. Our findings indicate that unlike LD formation, LD budding by inter-monolayer lipid exchange is a tension-independent process.
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Affiliation(s)
- Fatemeh Kazemisabet
- School of Mechanical Engineering, College of Engineering, University of Tehran, North Kargar St., 14399-57131 Tehran, Iran
| | - Arash Bahrami
- School of Mechanical Engineering, College of Engineering, University of Tehran, North Kargar St., 14399-57131 Tehran, Iran
| | - Rikhia Ghosh
- Department of Pharmacological Sciences, Icahn School of Medicine, Mount Sinai, New York 10029, USA
| | - Bartosz Różycki
- Institute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warsaw, Poland
| | - Amir H Bahrami
- UNAM-National Nanotechnology Research Center and Institute of Materials Science & Nanotechnology, Bilkent University, Ankara, Turkey.
- Living Matter Physics, Max Planck Institute for Dynamics and Self-Organization, 37077 Göttingen, Germany
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6
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Stribny J, Schneiter R. Binding of perilipin 3 to membranes containing diacylglycerol is mediated by conserved residues within its PAT domain. J Biol Chem 2023; 299:105384. [PMID: 37898398 PMCID: PMC10694602 DOI: 10.1016/j.jbc.2023.105384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2023] [Revised: 10/12/2023] [Accepted: 10/17/2023] [Indexed: 10/30/2023] Open
Abstract
Perilipins (PLINs) constitute an evolutionarily conserved family of proteins that specifically associate with the surface of lipid droplets (LDs). These proteins function in LD biogenesis and lipolysis and help to stabilize the surface of LDs. PLINs are typically composed of three different protein domains. They share an N-terminal PAT domain of unknown structure and function, a central region containing 11-mer repeats that form amphipathic helices, and a C-terminal domain that adopts a 4-helix bundle structure. How exactly these three distinct domains contribute to PLIN function remains to be determined. Here, we show that the N-terminal PAT domain of PLIN3 binds diacylglycerol (DAG), the precursor to triacylglycerol, a major storage lipid of LDs. PLIN3 and its PAT domain alone bind liposomes with micromolar affinity and PLIN3 binds artificial LDs containing low concentrations of DAG with nanomolar affinity. The PAT domain of PLIN3 is predicted to adopt an amphipathic triangular shaped structure. In silico ligand docking indicates that DAG binds to one of the highly curved regions within this domain. A conserved aspartic acid residue in the PAT domain, E86, is predicted to interact with DAG, and we found that its substitution abrogates high affinity binding of DAG as well as DAG-stimulated association with liposome and artificial LDs. These results indicate that the PAT domain of PLINs harbor specific lipid-binding properties that are important for targeting these proteins to the surface of LDs and to ER membrane domains enriched in DAG to promote LD formation.
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Affiliation(s)
- Jiri Stribny
- Department of Biology, University of Fribourg, Fribourg, Switzerland
| | - Roger Schneiter
- Department of Biology, University of Fribourg, Fribourg, Switzerland.
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7
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Kumari RM, Khatri A, Chaudhary R, Choudhary V. Concept of lipid droplet biogenesis. Eur J Cell Biol 2023; 102:151362. [PMID: 37742390 PMCID: PMC7615795 DOI: 10.1016/j.ejcb.2023.151362] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 09/15/2023] [Accepted: 09/18/2023] [Indexed: 09/26/2023] Open
Abstract
Lipid droplets (LD) are functionally conserved fat storage organelles found in all cell types. LDs have a unique structure comprising of a hydrophobic core of neutral lipids (fat), triacylglycerol (TAG) and cholesterol esters (CE) surrounded by a phospholipid monolayer. LD surface is decorated by a multitude of proteins and enzymes rendering this compartment functional. Accumulating evidence suggests that LDs originate from discrete ER-subdomains, demarcated by the lipodystrophy protein seipin, however, the mechanisms of which are not well understood. LD biogenesis factors together with biophysical properties of the ER membrane orchestrate spatiotemporal regulation of LD nucleation and growth at specific ER subdomains in response to metabolic cues. Defects in LD formation manifests in several human pathologies, including obesity, lipodystrophy, ectopic fat accumulation, and insulin resistance. Here, we review recent advances in understanding the molecular events during initial stages of eukaryotic LD assembly and discuss the critical role of factors that ensure fidelity of this process.
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Affiliation(s)
- R Mankamna Kumari
- Lipid Metabolism Laboratory, Department of Biotechnology, All India Institute of Medical Sciences (AIIMS), New Delhi 110029, India
| | - Amit Khatri
- Lipid Metabolism Laboratory, Department of Biotechnology, All India Institute of Medical Sciences (AIIMS), New Delhi 110029, India
| | - Ritika Chaudhary
- Lipid Metabolism Laboratory, Department of Biotechnology, All India Institute of Medical Sciences (AIIMS), New Delhi 110029, India
| | - Vineet Choudhary
- Lipid Metabolism Laboratory, Department of Biotechnology, All India Institute of Medical Sciences (AIIMS), New Delhi 110029, India.
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8
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Zhao P, Zhao Z, Yu Z, Chen L, Jin Y, Wu J, Ren Z. Application of synthetic lipid droplets in metabolic diseases. Clin Transl Med 2023; 13:e1441. [PMID: 37997538 PMCID: PMC10668006 DOI: 10.1002/ctm2.1441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 09/16/2023] [Accepted: 10/01/2023] [Indexed: 11/25/2023] Open
Abstract
BACKGROUND The study and synthesis of membrane organelles are becoming increasingly important, not only as simplified cellular models for corresponding molecular and metabolic studies but also for applications in synthetic biology of artificial cells and drug delivery vehicles. Lipid droplets (LDs) are central organelles in cellular lipid metabolism and are involved in almost all metabolic processes. Multiple studies have also demonstrated a high correlation between LDs and metabolic diseases. During these processes, LDs reveal a highly dynamic character, with their lipid fraction, protein composition and subcellular localisation constantly changing in response to metabolic demands. However, the molecular mechanisms underlying these functions have not been fully understood due to the limitations of cell biology approaches. Fortunately, developments in synthetic biology have provided a huge breakthrough for metabolism research, and methods for in vitro synthesis of LDs have been successfully established, with great advances in protein binding, lipid function, membrane dynamics and enzymatic reactions. AIMS AND METHODS In this review, we provide a comprehensive overview of the assembly and function of endogenous LDs, from the generation of lipid molecules to how they are assembled into LDs in the endoplasmic reticulum. In particular, we highlight two major classes of synthetic LD models for fabrication techniques and their recent advances in biology and explore their roles and challenges in achieving real applications of artificial LDs in the future.
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Affiliation(s)
- Pengxiang Zhao
- Key Laboratory of Agriculture Animal GeneticsBreeding and Reproduction of the Ministry of Education, College of Animal ScienceHuazhong Agricultural UniversityWuhanHubeiP. R. China
- College of Animal Science and TechnologyShandong Agricultural UniversityTaianShandongP. R. China
| | - Zichen Zhao
- Key Laboratory of Agriculture Animal GeneticsBreeding and Reproduction of the Ministry of Education, College of Animal ScienceHuazhong Agricultural UniversityWuhanHubeiP. R. China
| | - Ziwei Yu
- Key Laboratory of Agriculture Animal GeneticsBreeding and Reproduction of the Ministry of Education, College of Animal ScienceHuazhong Agricultural UniversityWuhanHubeiP. R. China
| | - Lupeng Chen
- Key Laboratory of Agriculture Animal GeneticsBreeding and Reproduction of the Ministry of Education, College of Animal ScienceHuazhong Agricultural UniversityWuhanHubeiP. R. China
| | - Yi Jin
- Key Laboratory of Agriculture Animal GeneticsBreeding and Reproduction of the Ministry of Education, College of Animal ScienceHuazhong Agricultural UniversityWuhanHubeiP. R. China
| | - Jian Wu
- Key Laboratory of Agriculture Animal GeneticsBreeding and Reproduction of the Ministry of Education, College of Animal ScienceHuazhong Agricultural UniversityWuhanHubeiP. R. China
- Frontiers Science Center for Animal Breeding and Sustainable ProductionWuhanHubeiP. R. China
| | - Zhuqing Ren
- Key Laboratory of Agriculture Animal GeneticsBreeding and Reproduction of the Ministry of Education, College of Animal ScienceHuazhong Agricultural UniversityWuhanHubeiP. R. China
- Frontiers Science Center for Animal Breeding and Sustainable ProductionWuhanHubeiP. R. China
- Hubei Hongshan LaboratoryWuhanHubeiP. R. China
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9
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Fines DM, Schichnes D, Knight M, Anaya-Sanchez A, Thuong N, Cox J, Stanley SA. Mycobacterial formation of intracellular lipid inclusions is a dynamic process associated with rapid replication. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.10.552809. [PMID: 37609245 PMCID: PMC10441389 DOI: 10.1101/2023.08.10.552809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/24/2023]
Abstract
Intracellular lipid inclusions (ILI) are triacylglyceride rich organelles produced by mycobacteria thought to serve as energy reservoirs. It is believed that ILI are formed as a result of a dosR mediated transition from replicative growth to non-replicating persistence (NRP). ILI rich Mycobacterium tuberculosis (Mtb) bacilli have been reported during infection and in sputum, establishing their importance in Mtb pathogenesis. Studies conducted in mycobacteria such as Mycobacterium smegmatis, Mycobacterium abscessus, or lab Mtb strains have demonstrated ILI formation in the presence of hypoxic, nitric oxide, nutrient limitation, or low nitrogen stress, conditions believed to emulate the host environment within which Mtb resides. Here, we show that M. marinum and clinical Mtb isolates make ILI during active replication in axenic culture independent of environmental stressors. By tracking ILI formation dynamics we demonstrate that ILI are quickly formed in the presence of fresh media or exogenous fatty acids but are rapidly depleted while bacteria are still actively replicating. We also show that the cell envelope is an alternate site for neutral lipid accumulation observed during stationary phase. In addition, we screen a panel of 60 clinical isolates and observe variation in ILI production during early log phase growth between and among Mtb lineages. Finally, we show that dosR expression level does not strictly correlate with ILI accumulation in fresh clinical isolates. Taken together, our data provide evidence of an active ILI formation pathway in replicating mycobacteria cultured in the absence of stressors, suggesting a decoupling of ILI formation from NRP.
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10
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Bombarda-Rocha V, Silva D, Badr-Eddine A, Nogueira P, Gonçalves J, Fresco P. Challenges in Pharmacological Intervention in Perilipins (PLINs) to Modulate Lipid Droplet Dynamics in Obesity and Cancer. Cancers (Basel) 2023; 15:4013. [PMID: 37568828 PMCID: PMC10417315 DOI: 10.3390/cancers15154013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 08/01/2023] [Accepted: 08/04/2023] [Indexed: 08/13/2023] Open
Abstract
Perilipins (PLINs) are the most abundant proteins in lipid droplets (LD). These LD-associated proteins are responsible for upgrading LD from inert lipid storage structures to fully functional organelles, fundamentally integrated in the lipid metabolism. There are five distinct perilipins (PLIN1-5), each with specific expression patterns and metabolic activation, but all capable of regulating the activity of lipases on LD. This plurality creates a complex orchestrated mechanism that is directly related to the healthy balance between lipogenesis and lipolysis. Given the essential role of PLINs in the modulation of the lipid metabolism, these proteins can become interesting targets for the treatment of lipid-associated diseases. Since reprogrammed lipid metabolism is a recognized cancer hallmark, and obesity is a known risk factor for cancer and other comorbidities, the modulation of PLINs could either improve existing treatments or create new opportunities for the treatment of these diseases. Even though PLINs have not been, so far, directly considered for pharmacological interventions, there are many established drugs that can modulate PLINs activity. Therefore, the aim of this study is to assess the involvement of PLINs in diseases related to lipid metabolism dysregulation and whether PLINs can be viewed as potential therapeutic targets for cancer and obesity.
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Affiliation(s)
- Victória Bombarda-Rocha
- Laboratory of Pharmacology, Department of Drug Sciences, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal; (V.B.-R.); (D.S.); (A.B.-E.); (P.N.); (P.F.)
- UCIBIO–Applied Molecular Biosciences Unit, Associate Laboratory i4HB, Institute for Health and Bioeconomy, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal
| | - Dany Silva
- Laboratory of Pharmacology, Department of Drug Sciences, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal; (V.B.-R.); (D.S.); (A.B.-E.); (P.N.); (P.F.)
- UCIBIO–Applied Molecular Biosciences Unit, Associate Laboratory i4HB, Institute for Health and Bioeconomy, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal
| | - Allal Badr-Eddine
- Laboratory of Pharmacology, Department of Drug Sciences, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal; (V.B.-R.); (D.S.); (A.B.-E.); (P.N.); (P.F.)
| | - Patrícia Nogueira
- Laboratory of Pharmacology, Department of Drug Sciences, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal; (V.B.-R.); (D.S.); (A.B.-E.); (P.N.); (P.F.)
- UCIBIO–Applied Molecular Biosciences Unit, Associate Laboratory i4HB, Institute for Health and Bioeconomy, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal
| | - Jorge Gonçalves
- Laboratory of Pharmacology, Department of Drug Sciences, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal; (V.B.-R.); (D.S.); (A.B.-E.); (P.N.); (P.F.)
- UCIBIO–Applied Molecular Biosciences Unit, Associate Laboratory i4HB, Institute for Health and Bioeconomy, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal
| | - Paula Fresco
- Laboratory of Pharmacology, Department of Drug Sciences, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal; (V.B.-R.); (D.S.); (A.B.-E.); (P.N.); (P.F.)
- UCIBIO–Applied Molecular Biosciences Unit, Associate Laboratory i4HB, Institute for Health and Bioeconomy, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal
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11
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Hüsler D, Stauffer P, Hilbi H. Tapping lipid droplets: A rich fat diet of intracellular bacterial pathogens. Mol Microbiol 2023; 120:194-209. [PMID: 37429596 DOI: 10.1111/mmi.15120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 06/21/2023] [Accepted: 06/22/2023] [Indexed: 07/12/2023]
Abstract
Lipid droplets (LDs) are dynamic and versatile organelles present in most eukaryotic cells. LDs consist of a hydrophobic core of neutral lipids, a phospholipid monolayer coat, and a variety of associated proteins. LDs are formed at the endoplasmic reticulum and have diverse roles in lipid storage, energy metabolism, membrane trafficking, and cellular signaling. In addition to their physiological cellular functions, LDs have been implicated in the pathogenesis of several diseases, including metabolic disorders, cancer, and infections. A number of intracellular bacterial pathogens modulate and/or interact with LDs during host cell infection. Members of the genera Mycobacterium, Legionella, Coxiella, Chlamydia, and Salmonella exploit LDs as a source of intracellular nutrients and membrane components to establish their distinct intracellular replicative niches. In this review, we focus on the biogenesis, interactions, and functions of LDs, as well as on their role in lipid metabolism of intracellular bacterial pathogens.
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Affiliation(s)
- Dario Hüsler
- Institute of Medical Microbiology, University of Zurich, Zurich, Switzerland
| | - Pia Stauffer
- Institute of Medical Microbiology, University of Zurich, Zurich, Switzerland
| | - Hubert Hilbi
- Institute of Medical Microbiology, University of Zurich, Zurich, Switzerland
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12
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Zhang Y, Liang X, Lian Q, Liu L, Zhang B, Dong Z, Liu K. Transcriptional analysis of the expression and prognostic value of lipid droplet-localized proteins in hepatocellular carcinoma. BMC Cancer 2023; 23:677. [PMID: 37464334 DOI: 10.1186/s12885-023-10987-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Accepted: 05/20/2023] [Indexed: 07/20/2023] Open
Abstract
The accumulation of lipid droplets (LDs) in hepatocytes is the main pathogenesis in nonalcoholic fatty liver disease (NAFLD), which is also the key risk factor for the progression of hepatocellular carcinoma (HCC). LDs behaviors are demonstrated to be associated with HCC advancement, and are tightly regulated by a subset protein localized on the surface of LDs. However, the role of LDs-localized protein in HCC has been rarely investigated. This study is focused on the transcriptional dynamic and prognostic value of LDs-localized protein in HCC. Firstly, we summarized the known LDs-localized proteins, which are demonstrated by immunofluorescence according to previous studies. Next, by the use of GEPIA/UALCAN/The Human Protein Atlas databases, we screened the transcriptional change in tumor and normal liver tissues, and found that 13 LDs-localized proteins may involve in the progression of HCC. Then we verified the transcriptional changes of 13 LDs-localized proteins by the use of HCC samples. Moreover, based on the assays of fatty liver of mice and human NAFLD liver samples, we found that the hepatic steatosis mainly contributed to the transcriptional change of selected LDs-localized proteins, indicating the involvement of these LDs-localized proteins in the negative role of NAFLD in HCC progression. Finally, we focused on the role of PLIN3 in HCC, and revealed that NAFLD status significantly promoted PLIN3 transcription in HCC tissue. Functional studies revealed that PLIN3 knockdown significantly limited the migration and chemosensitivity of hepatoma cells, suggesting the positive role of PLIN3 in HCC progression. Our study not only revealed the transcriptional change and prognostic value of lipid droplet-localized proteins in HCC, but also built the correlation between HCC and hepatic steatosis.
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Affiliation(s)
- Yize Zhang
- Precision Medicine Center, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
- Gene Hospital of Henan Province, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Xue Liang
- School of Life Science, Beijing University of Chinese Medicine, Beijing, China
| | - Qinghai Lian
- Cell-gene Therapy Translational Medicine Research Center, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Liwen Liu
- Precision Medicine Center, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
- Gene Hospital of Henan Province, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Baoyu Zhang
- Department of Neurosurgery, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China.
| | - Zihui Dong
- Precision Medicine Center, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
- Gene Hospital of Henan Province, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
| | - Kunpeng Liu
- Cell-gene Therapy Translational Medicine Research Center, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China.
- School of Medicine, Guangxi University, Nanning, Guangxi, China.
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13
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Khaddaj R, Stribny J, Cottier S, Schneiter R. Perilipin 3 promotes the formation of membrane domains enriched in diacylglycerol and lipid droplet biogenesis proteins. Front Cell Dev Biol 2023; 11:1116491. [PMID: 37465010 PMCID: PMC10350540 DOI: 10.3389/fcell.2023.1116491] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Accepted: 06/14/2023] [Indexed: 07/20/2023] Open
Abstract
Lipid droplets (LDs) serve as intracellular stores of energy-rich neutral lipids. LDs form at discrete sites in the endoplasmic reticulum (ER) and they remain closely associated with the ER during lipogenic growth and lipolytic consumption. Their hydrophobic neutral lipid core is covered by a monolayer of phospholipids, which harbors a specific set of proteins. This LD surface is coated and stabilized by perilipins, a family of soluble proteins that specifically target LDs from the cytosol. We have previously used chimeric fusion proteins between perilipins and integral ER membrane proteins to test whether proteins that are anchored to the ER bilayer could be dragged onto the LD monolayer. Expression of these chimeric proteins induces repositioning of the ER membrane around LDs. Here, we test the properties of membrane-anchored perilipins in cells that lack LDs. Unexpectedly, membrane-anchored perilipins induce expansion and vesiculation of the perinuclear membrane resulting in the formation of crescent-shaped membrane domains that harbor LD-like properties. These domains are stained by LD-specific lipophilic dyes, harbor LD marker proteins, and they transform into nascent LDs upon induction of neutral lipid synthesis. These ER domains are enriched in diacylglycerol (DAG) and in ER proteins that are important for early steps of LD biogenesis, including seipin and Pex30. Formation of the domains in vivo depends on DAG levels, and we show that perilipin 3 (PLIN3) binds to liposomes containing DAG in vitro. Taken together, these observations indicate that perilipin not only serve to stabilize the surface of mature LDs but that they are likely to exert a more active role in early steps of LD biogenesis at ER subdomains enriched in DAG, seipin, and neutral lipid biosynthetic enzymes.
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Affiliation(s)
- Rasha Khaddaj
- Department of Biology, University of Fribourg, Fribourg, Switzerland
| | - Jiri Stribny
- Department of Biology, University of Fribourg, Fribourg, Switzerland
| | - Stéphanie Cottier
- Department of Biology, University of Fribourg, Fribourg, Switzerland
| | - Roger Schneiter
- Department of Biology, University of Fribourg, Fribourg, Switzerland
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14
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Choi YM, Ajjaji D, Fleming KD, Borbat PP, Jenkins ML, Moeller BE, Fernando S, Bhatia SR, Freed JH, Burke JE, Thiam AR, Airola MV. Structural insights into perilipin 3 membrane association in response to diacylglycerol accumulation. Nat Commun 2023; 14:3204. [PMID: 37268630 PMCID: PMC10238389 DOI: 10.1038/s41467-023-38725-w] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Accepted: 05/12/2023] [Indexed: 06/04/2023] Open
Abstract
Lipid droplets (LDs) are dynamic organelles that contain an oil core mainly composed of triglycerides (TAG) that is surrounded by a phospholipid monolayer and LD-associated proteins called perilipins (PLINs). During LD biogenesis, perilipin 3 (PLIN3) is recruited to nascent LDs as they emerge from the endoplasmic reticulum. Here, we analyze how lipid composition affects PLIN3 recruitment to membrane bilayers and LDs, and the structural changes that occur upon membrane binding. We find that the TAG precursors phosphatidic acid and diacylglycerol (DAG) recruit PLIN3 to membrane bilayers and define an expanded Perilipin-ADRP-Tip47 (PAT) domain that preferentially binds DAG-enriched membranes. Membrane binding induces a disorder to order transition of alpha helices within the PAT domain and 11-mer repeats, with intramolecular distance measurements consistent with the expanded PAT domain adopting a folded but dynamic structure upon membrane binding. In cells, PLIN3 is recruited to DAG-enriched ER membranes, and this requires both the PAT domain and 11-mer repeats. This provides molecular details of PLIN3 recruitment to nascent LDs and identifies a function of the PAT domain of PLIN3 in DAG binding.
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Affiliation(s)
- Yong Mi Choi
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY, 11794, USA
| | - Dalila Ajjaji
- Laboratoire de Physique de l'École normale supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université Paris Cité, F-75005, Paris, France
| | - Kaelin D Fleming
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, V8N 1A1, Canada
| | - Peter P Borbat
- National Biomedical Resource for Advanced Electron Spin Resonance Technology (ACERT), Cornell University, Ithaca, NY, 14853, USA
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14853, USA
| | - Meredith L Jenkins
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, V8N 1A1, Canada
| | - Brandon E Moeller
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, V8N 1A1, Canada
| | - Shaveen Fernando
- Department of Chemistry, Stony Brook University, Stony Brook, NY, 11794, USA
| | - Surita R Bhatia
- Department of Chemistry, Stony Brook University, Stony Brook, NY, 11794, USA
| | - Jack H Freed
- National Biomedical Resource for Advanced Electron Spin Resonance Technology (ACERT), Cornell University, Ithaca, NY, 14853, USA
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14853, USA
| | - John E Burke
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, V8N 1A1, Canada.
- Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, British Columbia, V6T 1Z3, Canada.
| | - Abdou Rachid Thiam
- Laboratoire de Physique de l'École normale supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université Paris Cité, F-75005, Paris, France.
| | - Michael V Airola
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY, 11794, USA.
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15
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Zadoorian A, Du X, Yang H. Lipid droplet biogenesis and functions in health and disease. Nat Rev Endocrinol 2023:10.1038/s41574-023-00845-0. [PMID: 37221402 DOI: 10.1038/s41574-023-00845-0] [Citation(s) in RCA: 63] [Impact Index Per Article: 63.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/25/2023] [Indexed: 05/25/2023]
Abstract
Ubiquitous yet unique, lipid droplets are intracellular organelles that are increasingly being recognized for their versatility beyond energy storage. Advances uncovering the intricacies of their biogenesis and the diversity of their physiological and pathological roles have yielded new insights into lipid droplet biology. Despite these insights, the mechanisms governing the biogenesis and functions of lipid droplets remain incompletely understood. Moreover, the causal relationship between the biogenesis and function of lipid droplets and human diseases is poorly resolved. Here, we provide an update on the current understanding of the biogenesis and functions of lipid droplets in health and disease, highlighting a key role for lipid droplet biogenesis in alleviating cellular stresses. We also discuss therapeutic strategies of targeting lipid droplet biogenesis, growth or degradation that could be applied in the future to common diseases, such as cancer, hepatic steatosis and viral infection.
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Affiliation(s)
- Armella Zadoorian
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, Australia
| | - Ximing Du
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, Australia
| | - Hongyuan Yang
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, Australia.
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16
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Zhao Y, Dong Q, Geng Y, Ma C, Shao Q. Dynamic Regulation of Lipid Droplet Biogenesis in Plant Cells and Proteins Involved in the Process. Int J Mol Sci 2023; 24:ijms24087476. [PMID: 37108639 PMCID: PMC10138601 DOI: 10.3390/ijms24087476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2023] [Revised: 04/11/2023] [Accepted: 04/13/2023] [Indexed: 04/29/2023] Open
Abstract
Lipid droplets (LDs) are ubiquitous, dynamic organelles found in almost all organisms, including animals, protists, plants and prokaryotes. The cell biology of LDs, especially biogenesis, has attracted increasing attention in recent decades because of their important role in cellular lipid metabolism and other newly identified processes. Emerging evidence suggests that LD biogenesis is a highly coordinated and stepwise process in animals and yeasts, occurring at specific sites of the endoplasmic reticulum (ER) that are defined by both evolutionarily conserved and organism- and cell type-specific LD lipids and proteins. In plants, understanding of the mechanistic details of LD formation is elusive as many questions remain. In some ways LD biogenesis differs between plants and animals. Several homologous proteins involved in the regulation of animal LD formation in plants have been identified. We try to describe how these proteins are synthesized, transported to the ER and specifically targeted to LD, and how these proteins participate in the regulation of LD biogenesis. Here, we review current work on the molecular processes that control LD formation in plant cells and highlight the proteins that govern this process, hoping to provide useful clues for future research.
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Affiliation(s)
- Yiwu Zhao
- Shandong Provincial Key Laboratory of Plant Stress, College of Life Sciences, Shandong Normal University, Jinan 250358, China
| | - Qingdi Dong
- Shandong Provincial Key Laboratory of Plant Stress, College of Life Sciences, Shandong Normal University, Jinan 250358, China
| | - Yuhu Geng
- Shandong Provincial Key Laboratory of Plant Stress, College of Life Sciences, Shandong Normal University, Jinan 250358, China
| | - Changle Ma
- Shandong Provincial Key Laboratory of Plant Stress, College of Life Sciences, Shandong Normal University, Jinan 250358, China
| | - Qun Shao
- Shandong Provincial Key Laboratory of Plant Stress, College of Life Sciences, Shandong Normal University, Jinan 250358, China
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17
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Cinato M, Mardani I, Miljanovic A, Drevinge C, Laudette M, Bollano E, Henricsson M, Tolö J, Bauza Thorbrügge M, Levin M, Lindbom M, Arif M, Pacher P, Andersson L, Olofsson CS, Borén J, Levin MC. Cardiac Plin5 interacts with SERCA2 and promotes calcium handling and cardiomyocyte contractility. Life Sci Alliance 2023; 6:e202201690. [PMID: 36717246 PMCID: PMC9887753 DOI: 10.26508/lsa.202201690] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 01/17/2023] [Accepted: 01/17/2023] [Indexed: 01/31/2023] Open
Abstract
The adult heart develops hypertrophy to reduce ventricular wall stress and maintain cardiac function in response to an increased workload. Although pathological hypertrophy generally progresses to heart failure, physiological hypertrophy may be cardioprotective. Cardiac-specific overexpression of the lipid-droplet protein perilipin 5 (Plin5) promotes cardiac hypertrophy, but it is unclear whether this response is beneficial. We analyzed RNA-sequencing data from human left ventricle and showed that cardiac PLIN5 expression correlates with up-regulation of cardiac contraction-related processes. To investigate how elevated cardiac Plin5 levels affect cardiac contractility, we generated mice with cardiac-specific overexpression of Plin5 (MHC-Plin5 mice). These mice displayed increased left ventricular mass and cardiomyocyte size but preserved heart function. Quantitative proteomics identified sarcoplasmic/endoplasmic reticulum Ca2+ ATPase 2 (SERCA2) as a Plin5-interacting protein. In situ proximity ligation assay further confirmed the Plin5/SERCA2 interaction. Live imaging showed increases in intracellular Ca2+ release during contraction, Ca2+ removal during relaxation, and SERCA2 function in MHC-Plin5 versus WT cardiomyocytes. These results identify a role of Plin5 in improving cardiac contractility through enhanced Ca2+ signaling.
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Affiliation(s)
- Mathieu Cinato
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, Institute of Medicine, Sahlgrenska Academy at University of Gothenburgand Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Ismena Mardani
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, Institute of Medicine, Sahlgrenska Academy at University of Gothenburgand Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Azra Miljanovic
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, Institute of Medicine, Sahlgrenska Academy at University of Gothenburgand Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Christina Drevinge
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, Institute of Medicine, Sahlgrenska Academy at University of Gothenburgand Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Marion Laudette
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, Institute of Medicine, Sahlgrenska Academy at University of Gothenburgand Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Entela Bollano
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, Institute of Medicine, Sahlgrenska Academy at University of Gothenburgand Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Marcus Henricsson
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, Institute of Medicine, Sahlgrenska Academy at University of Gothenburgand Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Johan Tolö
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden
| | - Marcos Bauza Thorbrügge
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden
| | - Max Levin
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, Institute of Medicine, Sahlgrenska Academy at University of Gothenburgand Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Malin Lindbom
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, Institute of Medicine, Sahlgrenska Academy at University of Gothenburgand Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Muhammad Arif
- Laboratory of Cardiovascular Physiology and Tissue Injury, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
| | - Pal Pacher
- Laboratory of Cardiovascular Physiology and Tissue Injury, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
| | - Linda Andersson
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, Institute of Medicine, Sahlgrenska Academy at University of Gothenburgand Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Charlotta S Olofsson
- Department of Physiology/Metabolic Physiology, Institute of Neuroscience and Physiology, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden
| | - Jan Borén
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, Institute of Medicine, Sahlgrenska Academy at University of Gothenburgand Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Malin C Levin
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, Institute of Medicine, Sahlgrenska Academy at University of Gothenburgand Sahlgrenska University Hospital, Gothenburg, Sweden
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18
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Adult Triploid Rainbow Trout Can Adapt to Various Dietary Lipid Levels by Coordinating Metabolism in Different Tissues. Metabolites 2023; 13:metabo13030396. [PMID: 36984836 PMCID: PMC10057997 DOI: 10.3390/metabo13030396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Revised: 03/04/2023] [Accepted: 03/06/2023] [Indexed: 03/11/2023] Open
Abstract
Triploid rainbow trout can adapt to various dietary lipid levels; however, the mechanisms of systematic adaptation are not well understood. To investigate how adult triploid rainbow trout maintains lipid hemostasis under different exogenous lipid intake, a 77-day feeding trial was conducted. Diets with lipid contents of 20%, 25%, and 30% were formulated and fed to triploid rainbow trout with an initial weight of 3 ± 0.02 kg, and they were named L20, L25, and L30 group, respectively. Results showed that the condition factor, hepatosomatic index, liver color, and plasma triglyceride were comparable among three groups (p > 0.05), whereas the value of specific growth rate, viscerosomatic index, and liver glycogen content gradually increased with increasing dietary lipid level (p < 0.05). A significantly highest value of plasma glucose and nonesterified fatty acids were found in the L30 group (p < 0.05), whereas the significantly higher content of plasma total cholesterol, high-density lipoprotein–cholesterol, and low-density lipoprotein–cholesterol was found in the L25 group compared with those in L20 group (p < 0.05). As for lipid deposition, abdominal adipose tissue, and muscle were the main lipid storage place for triploid rainbow trout when tissues’ weight is taken into consideration. Overall quantitative PCR showed that the lipid transport and glycolysis were upregulated, and fatty acids oxidative was downregulated in liver when fish were fed low lipid diets. It meant that the liver was the primary lipid metabolizing organ to low lipid diet feeding, which could switch energy supply between glycolysis and fatty acids oxidation. Fish fed with a moderate dietary lipid level diet could increase lipid uptake and promote lipogenesis in muscle. Abdominal adipose tissue could efficiently uptake excess exogenous free fatty acid through upregulating fatty acid uptake and synthesis de novo and then storing it in the form of triglyceride. Excess lipid uptake is preferentially stored in abdominal adipose tissue through coordinated fatty acid uptake and fatty acid synthesis de novo as dietary lipid levels increased. In summary, triploid rainbow trout can adapt to various dietary lipid levels by coordinating metabolism in different tissues.
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19
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Qin ZL, Yao QF, Ren H, Zhao P, Qi ZT. Lipid Droplets and Their Participation in Zika Virus Infection. Int J Mol Sci 2022; 23:ijms232012584. [PMID: 36293437 PMCID: PMC9604050 DOI: 10.3390/ijms232012584] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 10/11/2022] [Accepted: 10/14/2022] [Indexed: 11/23/2022] Open
Abstract
Lipid droplets (LDs) are highly conserved and dynamic intracellular organelles. Their functions are not limited to serving as neutral lipid reservoirs; they also participate in non-energy storage functions, such as cell lipid metabolism, protection from cell stresses, maintaining protein homeostasis, and regulating nuclear function. During a Zika virus (ZIKV) infection, the viruses hijack the LDs to provide energy and lipid sources for viral replication. The co-localization of ZIKV capsid (C) protein with LDs supports its role as a virus replication platform and a key compartment for promoting the generation of progeny virus particles. However, in view of the multiple functions of LDs, their role in ZIKV infection needs further elucidation. Here, we review the basic mechanism of LD biogenesis and biological functions and discuss how ZIKV infection utilizes these effects of LDs to facilitate virus replication, along with the future application strategy of developing new antiviral drugs based on the interaction of ZIKV with LDs.
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20
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Xu H, Wang X, Tao R, Bi J, He X, Zhu F, Liu K, Xu Y, Li J. Optimal Stage for Cryotop Vitrification of Porcine Embryos. Cell Reprogram 2022; 24:132-141. [PMID: 35699425 DOI: 10.1089/cell.2022.0001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Different development stages of porcine embryos have different tolerance to low temperature. Therefore, we took the porcine embryos after parthenogenetic activation (PA) as the model, to explore the optimal development stage for vitrification during morula (D4), early blastocyst (D5), and expanded blastocyst (D6) after PA (D0). Embryos were observed with microscope and analyzed by different staining after cryo-recovery for 24 hours. The quality of embryos was damaged after vitrification, including embryonic nuclei, DNA, cytoskeleton, and organelles. The re-expansion rate at 24 hours of D5 embryos was significantly higher than those of D4 and D6 embryos (D5 vs. D4 vs. D6, 27.620 ± 0.041 vs. 7.809 ± 0.027 vs. 13.970 ± 0.032, p < 0.05). Therefore, D5 embryos were selected as research objects to explore the effect of vitrification on lipid in vitrified embryos. The results showed that the expression levels of perilipin PLIN3 messenger RNA (mRNA) and triacylglycerol synthesis-related genes AGPAT1 and DGAT mRNA are significantly reduced (p < 0.05). Vitrification affected lipid synthesis, which might have an irreversible impact on embryonic development. In conclusion, our data demonstrated that the optimal stage of vitrification was D5 for early blastocysts.
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Affiliation(s)
- Hongxia Xu
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, Jiangsu, China
| | - Xuguang Wang
- College of Animal Science, Xinjiang Agricultural University, Ulumuqi, Xinjiang, China
| | - Ruixin Tao
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, Jiangsu, China
| | - Jiaying Bi
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, Jiangsu, China
| | - Xu He
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, Jiangsu, China
| | - Fuquan Zhu
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, Jiangsu, China
| | - Ke Liu
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, Jiangsu, China
| | - Yinxue Xu
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, Jiangsu, China
| | - Juan Li
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, Jiangsu, China
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21
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Gong J, Peng Y, Yu J, Pei W, Zhang Z, Fan D, Liu L, Xiao X, Liu R, Lu Q, Li P, Shang H, Shi Y, Li J, Ge Q, Liu A, Deng X, Fan S, Pan J, Chen Q, Yuan Y, Gong W. Linkage and association analyses reveal that hub genes in energy-flow and lipid biosynthesis pathways form a cluster in upland cotton. Comput Struct Biotechnol J 2022; 20:1841-1859. [PMID: 35521543 PMCID: PMC9046884 DOI: 10.1016/j.csbj.2022.04.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 04/11/2022] [Accepted: 04/11/2022] [Indexed: 11/25/2022] Open
Abstract
Upland cotton is an important allotetraploid crop that provides both natural fiber for the textile industry and edible vegetable oil for the food or feed industry. To better understand the genetic mechanism that regulates the biosynthesis of storage oil in cottonseed, we identified the genes harbored in the major quantitative trait loci/nucleotides (QTLs/QTNs) of kernel oil content (KOC) in cottonseed via both multiple linkage analyses and genome-wide association studies (GWAS). In ‘CCRI70′ RILs, six stable QTLs were simultaneously identified by linkage analysis of CHIP and SLAF-seq strategies. In ‘0-153′ RILs, eight stable QTLs were detected by consensus linkage analysis integrating multiple strategies. In the natural panel, thirteen and eight loci were associated across multiple environments with two algorithms of GWAS. Within the confidence interval of a major common QTL on chromosome 3, six genes were identified as participating in the interaction network highly correlated with cottonseed KOC. Further observations of gene differential expression showed that four of the genes, LtnD, PGK, LPLAT1, and PAH2, formed hub genes and two of them, FER and RAV1, formed the key genes in the interaction network. Sequence variations in the coding regions of LtnD, FER, PGK, LPLAT1, and PAH2 genes may support their regulatory effects on oil accumulation in mature cottonseed. Taken together, clustering of the hub genes in the lipid biosynthesis interaction network provides new insights to understanding the mechanism of fatty acid biosynthesis and TAG assembly and to further genetic improvement projects for the KOC in cottonseeds.
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Affiliation(s)
- Juwu Gong
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang 455000, Henan, China
- Engineering Research Centre of Cotton, Ministry of Education, College of Agriculture, Xinjiang Agricultural University, 311 Nongda East Road, Urumqi 830052, Xinjiang, China
- School of Agricultural Sciences, Zhengzhou University, Zhengzhou 450001, Henan, China
| | - Yan Peng
- Third Division of the Xinjiang Production and Construction Corps Agricultural Research Institute, Tumushuke, Xijiang 843900, China
| | - Jiwen Yu
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang 455000, Henan, China
- School of Agricultural Sciences, Zhengzhou University, Zhengzhou 450001, Henan, China
| | - Wenfeng Pei
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang 455000, Henan, China
| | - Zhen Zhang
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang 455000, Henan, China
| | - Daoran Fan
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang 455000, Henan, China
| | - Linjie Liu
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang 455000, Henan, China
- Engineering Research Centre of Cotton, Ministry of Education, College of Agriculture, Xinjiang Agricultural University, 311 Nongda East Road, Urumqi 830052, Xinjiang, China
| | - Xianghui Xiao
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang 455000, Henan, China
- Engineering Research Centre of Cotton, Ministry of Education, College of Agriculture, Xinjiang Agricultural University, 311 Nongda East Road, Urumqi 830052, Xinjiang, China
| | - Ruixian Liu
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang 455000, Henan, China
- Engineering Research Centre of Cotton, Ministry of Education, College of Agriculture, Xinjiang Agricultural University, 311 Nongda East Road, Urumqi 830052, Xinjiang, China
| | - Quanwei Lu
- College of Biotechnology and Food Engineering, Anyang Institute of Technology, Anyang, China
| | - Pengtao Li
- College of Biotechnology and Food Engineering, Anyang Institute of Technology, Anyang, China
| | - Haihong Shang
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang 455000, Henan, China
- School of Agricultural Sciences, Zhengzhou University, Zhengzhou 450001, Henan, China
| | - Yuzhen Shi
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang 455000, Henan, China
- School of Agricultural Sciences, Zhengzhou University, Zhengzhou 450001, Henan, China
| | - Junwen Li
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang 455000, Henan, China
- School of Agricultural Sciences, Zhengzhou University, Zhengzhou 450001, Henan, China
| | - Qun Ge
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang 455000, Henan, China
| | - Aiying Liu
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang 455000, Henan, China
| | - Xiaoying Deng
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang 455000, Henan, China
| | - Senmiao Fan
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang 455000, Henan, China
| | - Jingtao Pan
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang 455000, Henan, China
| | - Quanjia Chen
- Engineering Research Centre of Cotton, Ministry of Education, College of Agriculture, Xinjiang Agricultural University, 311 Nongda East Road, Urumqi 830052, Xinjiang, China
| | - Youlu Yuan
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang 455000, Henan, China
- Engineering Research Centre of Cotton, Ministry of Education, College of Agriculture, Xinjiang Agricultural University, 311 Nongda East Road, Urumqi 830052, Xinjiang, China
- School of Agricultural Sciences, Zhengzhou University, Zhengzhou 450001, Henan, China
| | - Wankui Gong
- State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang 455000, Henan, China
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22
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Abstract
Lipid droplets (LDs) are ubiquitous organelles that store and supply lipids for energy metabolism, membrane synthesis and production of lipid-derived signaling molecules. While compositional differences in the phospholipid monolayer or neutral lipid core of LDs impact their metabolism and function, the proteome of LDs has emerged as a major influencer in all aspects of LD biology. The perilipins (PLINs) are the most studied and abundant proteins residing on the LD surface. This Cell Science at a Glance and the accompanying poster summarize our current knowledge of the common and unique features of the mammalian PLIN family of proteins, the mechanisms through which they affect cell metabolism and signaling, and their links to disease.
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Affiliation(s)
- Charles P. Najt
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Mahima Devarajan
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Douglas G. Mashek
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
- Department of Medicine, Division of Diabetes, Endocrinology and Metabolism, University of Minnesota, Minneapolis, MN 55455, USA
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23
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Zhang W, Xu L, Zhu L, Liu Y, Yang S, Zhao M. Lipid Droplets, the Central Hub Integrating Cell Metabolism and the Immune System. Front Physiol 2021; 12:746749. [PMID: 34925055 PMCID: PMC8678573 DOI: 10.3389/fphys.2021.746749] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2021] [Accepted: 11/08/2021] [Indexed: 12/16/2022] Open
Abstract
Lipid droplets (LDs) are commonly found in various biological cells and are organelles related to cell metabolism. LDs, the number and size of which are heterogeneous across cell type, are primarily composed of polar lipids and proteins on the surface with neutral lipids in the core. Neutral lipids stored in LDs can be degraded by lipolysis and lipophagocytosis, which are regulated by various proteins. The process of LD formation can be summarized in four steps. In addition to energy production, LDs play an extremely pivotal role in a variety of physiological and pathological processes, such as endoplasmic reticulum stress, lipid toxicity, storage of fat-soluble vitamins, regulation of oxidative stress, and reprogramming of cell metabolism. Interestingly, LDs, the hub of integration between metabolism and the immune system, are involved in antitumor immunity, anti-infective immunity (viruses, bacteria, parasites, etc.) and some metabolic immune diseases. Herein, we summarize the role of LDs in several major immune cells as elucidated in recent years, including T cells, dendritic cells, macrophages, mast cells, and neutrophils. Additionally, we analyze the role of the interaction between LDs and immune cells in two typical metabolic immune diseases: atherosclerosis and Mycobacterium tuberculosis infection.
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Affiliation(s)
- Wei Zhang
- Department of Pediatrics, Third Xiangya Hospital, Central South University, Changsha, China
- Xiangya Hospital, Central South University, Changsha, China
| | - Linyong Xu
- School of Life Sciences, Central South University, Changsha, China
| | - Ling Zhu
- School of Life Sciences, Central South University, Changsha, China
| | - Yifan Liu
- Department of Pediatrics, Third Xiangya Hospital, Central South University, Changsha, China
- Xiangya School of Medicine, Central South University, Changsha, China
| | - Siwei Yang
- Department of Pediatrics, Third Xiangya Hospital, Central South University, Changsha, China
- Xiangya School of Medicine, Central South University, Changsha, China
| | - Mingyi Zhao
- Department of Pediatrics, Third Xiangya Hospital, Central South University, Changsha, China
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24
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Hello from the other side: Membrane contact of lipid droplets with other organelles and subsequent functional implications. Prog Lipid Res 2021; 85:101141. [PMID: 34793861 DOI: 10.1016/j.plipres.2021.101141] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 11/10/2021] [Accepted: 11/10/2021] [Indexed: 02/06/2023]
Abstract
Lipid droplets (LDs) are ubiquitous organelles that play crucial roles in response to physiological and environmental cues. The identification of several neutral lipid synthesizing and regulatory protein complexes have propelled significant advance on the mechanisms of LD biogenesis in the endoplasmic reticulum (ER). Increasing evidence suggests that distinct proteins and regulatory factors, which localize to membrane contact sites (MCS), are involved not only in interorganellar lipid exchange and transport, but also function in other important cellular processes, including autophagy, mitochondrial dynamics and inheritance, ion signaling and inter-regulation of these MCS. More and more tethers and molecular determinants are associated to MCS and to a diversity of cellular and pathophysiological processes, demonstrating the dynamics and importance of these junctions in health and disease. The conjugation of lipids with proteins in supramolecular complexes is known to be paramount for many biological processes, namely membrane biosynthesis, cell homeostasis, regulation of organelle division and biogenesis, and cell growth. Ultimately, this physical organization allows the contact sites to function as crucial metabolic hubs that control the occurrence of chemical reactions. This leads to biochemical and metabolite compartmentalization for the purposes of energetic efficiency and cellular homeostasis. In this review, we will focus on the structural and functional aspects of LD-organelle interactions and how they ensure signaling exchange and metabolites transfer between organelles.
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25
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Ajjaji D, Ben M'barek K, Boson B, Omrane M, Gassama-Diagne A, Blaud M, Penin F, Diaz E, Ducos B, Cosset FL, Thiam AR. Hepatitis C virus core protein uses triacylglycerols to fold onto the endoplasmic reticulum membrane. Traffic 2021; 23:63-80. [PMID: 34729868 DOI: 10.1111/tra.12825] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2021] [Revised: 10/16/2021] [Accepted: 11/01/2021] [Indexed: 12/12/2022]
Abstract
Lipid droplets (LDs) are involved in viral infections, but exactly how remains unclear. Here, we study the hepatitis C virus (HCV) whose core capsid protein binds to LDs but is also involved in the assembly of virions at the endoplasmic reticulum (ER) bilayer. We found that the amphipathic helix-containing domain of core, D2, senses triglycerides (TGs) rather than LDs per se. In the absence of LDs, D2 can bind to the ER membrane but only if TG molecules are present in the bilayer. Accordingly, the pharmacological inhibition of the diacylglycerol O-acyltransferase enzymes, mediating TG synthesis in the ER, inhibits D2 association with the bilayer. We found that TG molecules enable D2 to fold into alpha helices. Sequence analysis reveals that D2 resembles the apoE lipid-binding region. Our data support that TG in LDs promotes the folding of core, which subsequently relocalizes to contiguous ER regions. During this motion, core may carry TG molecules to these regions where HCV lipoviroparticles likely assemble. Consistent with this model, the inhibition of Arf1/COPI, which decreases LD surface accessibility to proteins and ER-LD material exchange, severely impedes the assembly of virions. Altogether, our data uncover a critical function of TG in the folding of core and HCV replication and reveals, more broadly, how TG accumulation in the ER may provoke the binding of soluble amphipathic helix-containing proteins to the ER bilayer.
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Affiliation(s)
- Dalila Ajjaji
- Laboratoire de Physique de l'École Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris, 24 rue Lhomond, Paris, 75005, France
| | - Kalthoum Ben M'barek
- Laboratoire de Physique de l'École Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris, 24 rue Lhomond, Paris, 75005, France
| | - Bertrand Boson
- CIRI-Centre International de Recherche en Infectiologie, Univ Lyon, Université Claude Bernard Lyon 1, Inserm, U1111, CNRS, UMR5308, ENS Lyon, Lyon, France
| | - Mohyeddine Omrane
- Laboratoire de Physique de l'École Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris, 24 rue Lhomond, Paris, 75005, France
| | - Ama Gassama-Diagne
- INSERM, Unité 1193, Villejuif, France.,Université Paris-Sud, UMR-S 1193, Villejuif, France
| | - Magali Blaud
- Université de Paris, CiTCoM, CNRS, Paris, France
| | - François Penin
- Institut de Biologie et Chimie des Protéines, Bases Moléculaires et Structurales des Systèmes Infectieux, UMR 5086, CNRS, Labex Ecofect, University of Lyon, Lyon, France
| | - Elise Diaz
- High Throughput qPCR Core Facility of the ENS, IBENS, PSL Research University, Paris, France
| | - Bertrand Ducos
- Laboratoire de Physique de l'École Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris, 24 rue Lhomond, Paris, 75005, France.,High Throughput qPCR Core Facility of the ENS, IBENS, PSL Research University, Paris, France
| | - François-Loïc Cosset
- CIRI-Centre International de Recherche en Infectiologie, Univ Lyon, Université Claude Bernard Lyon 1, Inserm, U1111, CNRS, UMR5308, ENS Lyon, Lyon, France
| | - Abdou Rachid Thiam
- Laboratoire de Physique de l'École Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris, 24 rue Lhomond, Paris, 75005, France
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26
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Sterols are required for the coordinated assembly of lipid droplets in developing seeds. Nat Commun 2021; 12:5598. [PMID: 34552075 PMCID: PMC8458542 DOI: 10.1038/s41467-021-25908-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 09/09/2021] [Indexed: 12/23/2022] Open
Abstract
Lipid droplets (LDs) are intracellular organelles critical for energy storage and lipid metabolism. They are typically composed of an oil core coated by a monolayer of phospholipids and proteins such as oleosins. The mechanistic details of LD biogenesis remain poorly defined. However, emerging evidence suggest that their formation is a spatiotemporally regulated process, occurring at specific sites of the endoplasmic reticulum defined by a specific set of lipids and proteins. Here, we show that sterols are required for formation of oleosin-coated LDs in Arabidopsis. Analysis of sterol pathway mutants revealed that deficiency in several ∆5-sterols accounts for the phenotype. Importantly, mutants deficient in these sterols also display reduced LD number, increased LD size and reduced oil content in seeds. Collectively, our data reveal a role of sterols in coordinating the synthesis of oil and oleosins and their assembly into LDs, highlighting the importance of membrane lipids in regulating LD biogenesis. Lipid droplet biogenesis originates at the endoplasmic reticulum and is defined by a specific set of lipids and proteins. Here, the authors show that sterols play an important role in coordinating oil and oleosin biosynthesis for the formation of lipid droplets in plant leaves and seeds.
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27
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Wilson MH, Ekker SC, Farber SA. Imaging cytoplasmic lipid droplets in vivo with fluorescent perilipin 2 and perilipin 3 knock-in zebrafish. eLife 2021; 10:e66393. [PMID: 34387191 PMCID: PMC8460263 DOI: 10.7554/elife.66393] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Accepted: 08/10/2021] [Indexed: 12/26/2022] Open
Abstract
Cytoplasmic lipid droplets are highly dynamic storage organelles that are critical for cellular lipid homeostasis. While the molecular details of lipid droplet dynamics are a very active area of investigation, this work has been primarily performed in cultured cells. Taking advantage of the powerful transgenic and in vivo imaging opportunities available in zebrafish, we built a suite of tools to study lipid droplets in real time from the subcellular to the whole organism level. Fluorescently tagging the lipid droplet-associated proteins, perilipin 2 and perilipin 3, in the endogenous loci permits visualization of lipid droplets in the intestine, liver, and adipose tissue. Using these tools, we found that perilipin 3 is rapidly loaded on intestinal lipid droplets following a high-fat meal and later replaced by perilipin 2. These powerful new tools will facilitate studies on the role of lipid droplets in different tissues, under different genetic and physiological manipulations, and in a variety of human disease models.
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Affiliation(s)
- Meredith H Wilson
- Carnegie Institution for Science Department of EmbryologyBaltimoreUnited States
| | - Stephen C Ekker
- Department of Biochemistry and Molecular Biology, Mayo ClinicRochesterUnited States
| | - Steven A Farber
- Carnegie Institution for Science Department of EmbryologyBaltimoreUnited States
- Johns Hopkins University Department of BiologyBaltimoreUnited States
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28
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Hussain SS, Tran TM, Ware TB, Luse MA, Prevost CT, Ferguson AN, Kashatus JA, Hsu KL, Kashatus DF. RalA and PLD1 promote lipid droplet growth in response to nutrient withdrawal. Cell Rep 2021; 36:109451. [PMID: 34320341 PMCID: PMC8344381 DOI: 10.1016/j.celrep.2021.109451] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 06/04/2021] [Accepted: 07/02/2021] [Indexed: 01/22/2023] Open
Abstract
Lipid droplets (LDs) are dynamic organelles that undergo dynamic changes in response to changing cellular conditions. During nutrient depletion, LD numbers increase to protect cells against toxic fatty acids generated through autophagy and provide fuel for beta-oxidation. However, the precise mechanisms through which these changes are regulated have remained unclear. Here, we show that the small GTPase RalA acts downstream of autophagy to directly facilitate LD growth during nutrient depletion. Mechanistically, RalA performs this function through phospholipase D1 (PLD1), an enzyme that converts phosphatidylcholine (PC) to phosphatidic acid (PA) and that is recruited to lysosomes during nutrient stress in a RalA-dependent fashion. RalA inhibition prevents recruitment of the LD-associated protein perilipin 3, which is required for LD growth. Our data support a model in which RalA recruits PLD1 to lysosomes during nutrient deprivation to promote the localized production of PA and the recruitment of perilipin 3 to expanding LDs.
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Affiliation(s)
- Syed S Hussain
- Department of Microbiology, Immunology and Cancer Biology, University of Virginia Health System, Charlottesville, VA 22908, USA
| | - Tuyet-Minh Tran
- Department of Microbiology, Immunology and Cancer Biology, University of Virginia Health System, Charlottesville, VA 22908, USA
| | - Timothy B Ware
- Department of Chemistry, University of Virginia, Charlottesville, VA 22904, USA
| | - Melissa A Luse
- Department of Microbiology, Immunology and Cancer Biology, University of Virginia Health System, Charlottesville, VA 22908, USA
| | - Christopher T Prevost
- Department of Microbiology, Immunology and Cancer Biology, University of Virginia Health System, Charlottesville, VA 22908, USA
| | - Ashley N Ferguson
- Department of Microbiology, Immunology and Cancer Biology, University of Virginia Health System, Charlottesville, VA 22908, USA
| | - Jennifer A Kashatus
- Department of Microbiology, Immunology and Cancer Biology, University of Virginia Health System, Charlottesville, VA 22908, USA
| | - Ku-Lung Hsu
- Department of Chemistry, University of Virginia, Charlottesville, VA 22904, USA; University of Virginia Cancer Center, University of Virginia Health System, Charlottesville, VA 22903, USA
| | - David F Kashatus
- Department of Microbiology, Immunology and Cancer Biology, University of Virginia Health System, Charlottesville, VA 22908, USA; University of Virginia Cancer Center, University of Virginia Health System, Charlottesville, VA 22903, USA.
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29
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Zhao Y, Albrecht E, Li Z, Schregel J, Sciascia QL, Metges CC, Maak S. Distinct Roles of Perilipins in the Intramuscular Deposition of Lipids in Glutamine-Supplemented, Low-, and Normal-Birth-Weight Piglets. Front Vet Sci 2021; 8:633898. [PMID: 34235195 PMCID: PMC8257002 DOI: 10.3389/fvets.2021.633898] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Accepted: 05/10/2021] [Indexed: 11/13/2022] Open
Abstract
Piglets with low birth weight (LBW) usually have reduced muscle mass and increased lipid deposition compared with their normal-birth-weight (NBW) littermates. Supplementation of piglets with amino acids during the first days of life may improve muscle growth and simultaneously alter the intramuscular lipid deposition. The aim of the current study was to investigate the influence of glutamine (Gln) supplementation during the early suckling period on lipid deposition in the longissimus muscle (MLD) and the role of different perilipin (PLIN) family members in this process. Four groups were generated consisting of 72 male LBW piglets and 72 NBW littermates. Piglets were supplemented with either 1 g Gln/kg body weight or an isonitrogenous amount of alanine (Ala) between days post natum (dpn) 1 and 12. Twelve piglets per group were slaughtered at 5, 12, and 26 dpn, and muscle tissue was collected. Perilipins were localized by immunohistochemistry in muscle sections. The mRNA and protein abundances of PLIN family members and related lipases were quantified by quantitative RT-PCR (qPCR) and western blots, respectively. While PLIN1 was localized around lipid droplets in mature and developing adipocytes, PLIN2 was localized at intramyocellular lipid droplets, PLIN3 and 4 at cell membranes of muscle fibers and adipocytes, and PLIN5 in the cytoplasm of undefined cells. The western blot results indicated higher protein abundances of PLIN2, 3, 4, and 5 in LBW piglets (p < 0.05) at 5 dpn compared with their NBW littermates independent of supplementation, while not directly reflecting the mRNA expression levels. The mRNA abundance of PLIN2 was lower while PLIN4 was higher in piglets at 26 dpn in comparison with piglets at 5 dpn (p < 0.01). Relative mRNA expression of LPL and CGI-58 was lowest in piglets at 5 dpn (p < 0.001). However, ATGL mRNA was not influenced by birth weight or supplementation, but the Spearman correlation coefficient analysis revealed close correlations with PLIN2, 4, and 5 mRNA at 5 and 26 dpn (r > 0.5, p < 0.001). The results indicated the importance of birth weight and age for intramuscular lipid deposition and different roles of PLIN family members in this process, but no clear modulating effect of Gln supplementation.
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Affiliation(s)
- Yaolu Zhao
- Institute of Muscle Biology and Growth, Leibniz Institute for Farm Animal Biology (FBN), Dummerstorf, Germany
| | - Elke Albrecht
- Institute of Muscle Biology and Growth, Leibniz Institute for Farm Animal Biology (FBN), Dummerstorf, Germany
| | - Zeyang Li
- Institute of Nutritional Physiology "Oskar Kellner", Leibniz Institute for Farm Animal Biology (FBN), Dummerstorf, Germany
| | - Johannes Schregel
- Institute of Nutritional Physiology "Oskar Kellner", Leibniz Institute for Farm Animal Biology (FBN), Dummerstorf, Germany
| | - Quentin L Sciascia
- Institute of Nutritional Physiology "Oskar Kellner", Leibniz Institute for Farm Animal Biology (FBN), Dummerstorf, Germany
| | - Cornelia C Metges
- Institute of Nutritional Physiology "Oskar Kellner", Leibniz Institute for Farm Animal Biology (FBN), Dummerstorf, Germany
| | - Steffen Maak
- Institute of Muscle Biology and Growth, Leibniz Institute for Farm Animal Biology (FBN), Dummerstorf, Germany
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30
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Zoni V, Khaddaj R, Lukmantara I, Shinoda W, Yang H, Schneiter R, Vanni S. Seipin accumulates and traps diacylglycerols and triglycerides in its ring-like structure. Proc Natl Acad Sci U S A 2021; 118:e2017205118. [PMID: 33674387 PMCID: PMC7958289 DOI: 10.1073/pnas.2017205118] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Lipid droplets (LDs) are intracellular organelles responsible for lipid storage, and they emerge from the endoplasmic reticulum (ER) upon the accumulation of neutral lipids, mostly triglycerides (TG), between the two leaflets of the ER membrane. LD biogenesis takes place at ER sites that are marked by the protein seipin, which subsequently recruits additional proteins to catalyze LD formation. Deletion of seipin, however, does not abolish LD biogenesis, and its precise role in controlling LD assembly remains unclear. Here, we use molecular dynamics simulations to investigate the molecular mechanism through which seipin promotes LD formation. We find that seipin clusters TG, as well as its precursor diacylglycerol, inside its unconventional ring-like oligomeric structure and that both its luminal and transmembrane regions contribute to this process. This mechanism is abolished upon mutations of polar residues involved in protein-TG interactions into hydrophobic residues. Our results suggest that seipin remodels the membrane of specific ER sites to prime them for LD biogenesis.
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Affiliation(s)
- Valeria Zoni
- Department of Biology, University of Fribourg, 1700 Fribourg, Switzerland
| | - Rasha Khaddaj
- Department of Biology, University of Fribourg, 1700 Fribourg, Switzerland
| | - Ivan Lukmantara
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW 2052, Australia
| | - Wataru Shinoda
- Department of Materials Chemistry, Nagoya University, Chikusa-ku, 464-8603 Nagoya, Japan
| | - Hongyuan Yang
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW 2052, Australia
| | - Roger Schneiter
- Department of Biology, University of Fribourg, 1700 Fribourg, Switzerland
| | - Stefano Vanni
- Department of Biology, University of Fribourg, 1700 Fribourg, Switzerland;
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31
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Tanaka T, Nakano T, Hozumi Y, Martelli AM, Goto K. Regulation of p53 and NF-κB transactivation activities by DGKζ in catalytic activity-dependent and -independent manners. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2021; 1868:118953. [PMID: 33450306 DOI: 10.1016/j.bbamcr.2021.118953] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 12/15/2020] [Accepted: 01/02/2021] [Indexed: 01/03/2023]
Abstract
Diacylglycerol kinase (DGK) constitutes a family of enzymes that phosphorylate diacylglycerol to phosphatidic acid (PA). These lipids serve as second messengers, thereby activating distinct downstream cascades and different cellular responses. Therefore, DG-to-PA conversion activity induces a phase transition of signaling pathways. One member of the family, DGKζ, is involved closely with stress responses. Morphological data showing that DGKζ localizes predominantly to the nucleus and that it shuttles between the nucleus and the cytoplasm implicate DGKζ in the regulation of transcription factors during stress responses. Tumor suppressor p53 and NF-κB are major stress-responsive transcription factors. They exert opposing effects on cellular pathophysiology. Herein, we summarize DGKζ catalytic activity-dependent and -independent regulatory mechanisms of p53 and NF-κB transactivation activities, including p53 degradation and NF-κB nuclear translocation. We also discuss how each component of DGKζ-interacting protein complex modulates the specificity and selectivity of target gene expression.
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Affiliation(s)
- Toshiaki Tanaka
- Department of Anatomy and Cell Biology, Yamagata University School of Medicine, Yamagata 990-9585, Japan.
| | - Tomoyuki Nakano
- Department of Anatomy and Cell Biology, Yamagata University School of Medicine, Yamagata 990-9585, Japan
| | - Yasukazu Hozumi
- Department of Cell Biology and Morphology, Akita University Graduate School of Medicine, Akita 010-8543, Japan
| | - Alberto M Martelli
- Department of Biomedical and Neuromotor Sciences, University of Bologna, via Irnerio 48, 40126 Bologna, Italy
| | - Kaoru Goto
- Department of Anatomy and Cell Biology, Yamagata University School of Medicine, Yamagata 990-9585, Japan.
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32
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Chorlay A, Thiam AR. Neutral lipids regulate amphipathic helix affinity for model lipid droplets. J Cell Biol 2020; 219:133864. [PMID: 32328636 PMCID: PMC7147095 DOI: 10.1083/jcb.201907099] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Revised: 12/14/2019] [Accepted: 01/27/2020] [Indexed: 02/07/2023] Open
Abstract
Cellular lipid droplets (LDs) have a neutral lipid core shielded from the aqueous environment by a phospholipid monolayer containing proteins. These proteins define the biological functions of LDs, and most of them bear amphipathic helices (AH), which can selectively target to LDs, or to LD subsets. How such binding preference happens remains poorly understood. Here, we found that artificial LDs made of different neutral lipids but presenting equal phospholipid packing densities differentially recruit AHs. Varying the phospholipid density shifts the binding levels, but the differential recruitment is unchanged. We found that the binding level of AHs is defined by their interaction preference with neutral lipids and ability to decrease surface tension. The phospholipid packing level regulates mainly the amount of neutral lipid accessible. Therefore, it is the hydrophobic nature of the phospholipid packing voids that controls the binding level of AHs. Our data bring us a major step closer to understanding the binding selectivity of AHs to lipid membranes.
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Affiliation(s)
- Aymeric Chorlay
- Laboratoire de Physique de l'Ecole Normale Supérieure, ENS, Université PSL, Centre National de la Recherche Scientifique, Sorbonne Université, Université de Paris, Paris, France
| | - Abdou Rachid Thiam
- Laboratoire de Physique de l'Ecole Normale Supérieure, ENS, Université PSL, Centre National de la Recherche Scientifique, Sorbonne Université, Université de Paris, Paris, France
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33
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Teixeira V, Maciel P, Costa V. Leading the way in the nervous system: Lipid Droplets as new players in health and disease. Biochim Biophys Acta Mol Cell Biol Lipids 2020; 1866:158820. [PMID: 33010453 DOI: 10.1016/j.bbalip.2020.158820] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 09/01/2020] [Accepted: 09/21/2020] [Indexed: 12/28/2022]
Abstract
Lipid droplets (LDs) are ubiquitous fat storage organelles composed of a neutral lipid core, comprising triacylglycerols (TAG) and sterol esters (SEs), surrounded by a phospholipid monolayer membrane with several decorating proteins. Recently, LD biology has come to the foreground of research due to their importance for energy homeostasis and cellular stress response. As aberrant LD accumulation and lipid depletion are hallmarks of numerous diseases, addressing LD biogenesis and turnover provides a new framework for understanding disease-related mechanisms. Here we discuss the potential role of LDs in neurodegeneration, while making some predictions on how LD imbalance can contribute to pathophysiology in the brain.
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Affiliation(s)
- Vitor Teixeira
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade of Porto, Porto, Portugal; IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal.
| | - Patrícia Maciel
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal; ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Vítor Costa
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade of Porto, Porto, Portugal; IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal; ICBAS, Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Porto, Portugal
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34
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Lipid Stores and Lipid Metabolism Associated Gene Expression in Porcine and Bovine Parthenogenetic Embryos Revealed by Fluorescent Staining and RNA-seq. Int J Mol Sci 2020; 21:ijms21186488. [PMID: 32899450 PMCID: PMC7555686 DOI: 10.3390/ijms21186488] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 09/03/2020] [Accepted: 09/03/2020] [Indexed: 12/27/2022] Open
Abstract
Compared to other mammalian species, porcine oocytes and embryos are characterized by large amounts of lipids stored mainly in the form of droplets in the cytoplasm. The amount and the morphology of lipid droplets (LD) change throughout the preimplantation development, however, relatively little is known about expression of genes involved in lipid metabolism of early embryos. We compared porcine and bovine blastocyst stage embryos as well as dissected inner cell mass (ICM) and trophoblast (TE) cell populations with regard to lipid droplet storage and expression of genes functionally annotated to selected lipid gene ontology terms using RNA-seq. Comparing the number and the volume occupied by LD between bovine and porcine blastocysts, we have found significant differences both at the level of single embryo and a single blastomere. Aside from different lipid content, we found that embryos regulate the lipid metabolism differentially at the gene expression level. Out of 125 genes, we found 73 to be differentially expressed between entire porcine and bovine blastocyst, and 36 and 51 to be divergent between ICM and TE cell lines. We noticed significant involvement of cholesterol and ganglioside metabolism in preimplantation embryos, as well as a possible shift towards glucose, rather than pyruvate dependence in bovine embryos. A number of genes like DGAT1, CD36 or NR1H3 may serve as lipid associated markers indicating distinct regulatory mechanisms, while upregulated PLIN2, APOA1, SOAT1 indicate significant function during blastocyst formation and cell differentiation in both models.
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35
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Jevons EFP, Gejl KD, Strauss JA, Ørtenblad N, Shepherd SO. Skeletal muscle lipid droplets are resynthesized before being coated with perilipin proteins following prolonged exercise in elite male triathletes. Am J Physiol Endocrinol Metab 2020; 318:E357-E370. [PMID: 31935113 DOI: 10.1152/ajpendo.00399.2019] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Intramuscular triglycerides (IMTG) are a key substrate during prolonged exercise, but little is known about the rate of IMTG resynthesis in the postexercise period. We investigated the hypothesis that the distribution of the lipid droplet (LD)-associated perilipin (PLIN) proteins is linked to IMTG storage following exercise. Fourteen elite male triathletes (27 ± 1 yr, 66.5 ± 1.3 mL·kg-1·min-1) completed 4 h of moderate-intensity cycling. During the first 4 h of recovery, subjects received either carbohydrate or H2O, after which both groups received carbohydrate. Muscle biopsies collected pre- and postexercise and 4 and 24 h postexercise were analyzed using confocal immunofluorescence microscopy for fiber type-specific IMTG content and PLIN distribution with LDs. Exercise reduced IMTG content in type I fibers (-53%, P = 0.002), with no change in type IIa fibers. During the first 4 h of recovery, IMTG content increased in type I fibers (P = 0.014), but was not increased more after 24 h, where it was similar to baseline levels in both conditions. During recovery the number of LDs labeled with PLIN2 (70%), PLIN3 (63%), and PLIN5 (62%; all P < 0.05) all increased in type I fibers. Importantly, the increase in LDs labeled with PLIN proteins only occurred at 24 h postexercise. In conclusion, IMTG resynthesis occurs rapidly in type I fibers following prolonged exercise in highly trained individuals. Furthermore, increases in IMTG content following exercise preceded an increase in the number of LDs labeled with PLIN proteins. These data, therefore, suggest that the PLIN proteins do not play a key role in postexercise IMTG resynthesis.
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Affiliation(s)
- Emily F P Jevons
- Research Institute of Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | - Kasper D Gejl
- Department of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark
| | - Juliette A Strauss
- Research Institute of Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | - Niels Ørtenblad
- Department of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark
| | - Sam O Shepherd
- Research Institute of Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom
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36
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Shao Q, Liu X, Su T, Ma C, Wang P. New Insights Into the Role of Seed Oil Body Proteins in Metabolism and Plant Development. FRONTIERS IN PLANT SCIENCE 2019; 10:1568. [PMID: 31921234 PMCID: PMC6914826 DOI: 10.3389/fpls.2019.01568] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Accepted: 11/08/2019] [Indexed: 05/10/2023]
Abstract
Oil bodies (OBs) are ubiquitous dynamic organelles found in plant seeds. They have attracted increasing attention recently because of their important roles in plant physiology. First, the neutral lipids stored within these organelles serve as an initial, essential source of energy and carbon for seed germination and post-germinative growth of the seedlings. Secondly, they are involved in many other cellular processes such as stress responses, lipid metabolism, organ development, and hormone signaling. The biological functions of seed OBs are dependent on structural proteins, principally oleosins, caleosins, and steroleosins, which are embedded in the OB phospholipid monolayer. Oleosin and caleosin proteins are specific to plants and mainly act as OB structural proteins and are important for the biogenesis, stability, and dynamics of the organelle; whereas steroleosin proteins are also present in mammals and play an important role in steroid hormone metabolism and signaling. Significant progress using new genetic, biochemical, and imaging technologies has uncovered the roles of these proteins. Here, we review recent work on the structural or metabolic roles of these proteins in OB biogenesis, stabilization and degradation, lipid homeostasis and mobilization, hormone signal transduction, stress defenses, and various aspects of plant growth and development.
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Affiliation(s)
| | | | | | - Changle Ma
- Shandong Provincial Key Laboratory of Plant Stress, College of Life Sciences, Shandong Normal University, Jinan, China
| | - Pingping Wang
- Shandong Provincial Key Laboratory of Plant Stress, College of Life Sciences, Shandong Normal University, Jinan, China
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37
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Soste M, Charmpi K, Lampert F, Gerez JA, van Oostrum M, Malinovska L, Boersema PJ, Prymaczok NC, Riek R, Peter M, Vanni S, Beyer A, Picotti P. Proteomics-Based Monitoring of Pathway Activity Reveals that Blocking Diacylglycerol Biosynthesis Rescues from Alpha-Synuclein Toxicity. Cell Syst 2019; 9:309-320.e8. [PMID: 31521608 PMCID: PMC6859835 DOI: 10.1016/j.cels.2019.07.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 04/17/2019] [Accepted: 07/23/2019] [Indexed: 12/26/2022]
Abstract
Proteinaceous inclusions containing alpha-synuclein (α-Syn) have been implicated in neuronal toxicity in Parkinson's disease, but the pathways that modulate toxicity remain enigmatic. Here, we used a targeted proteomic assay to simultaneously measure 269 pathway activation markers and proteins deregulated by α-Syn expression across a panel of 33 Saccharomyces cerevisiae strains that genetically modulate α-Syn toxicity. Applying multidimensional linear regression analysis to these data predicted Pah1, a phosphatase that catalyzes conversion of phosphatidic acid to diacylglycerol at the endoplasmic reticulum membrane, as an effector of rescue. Follow-up studies demonstrated that inhibition of Pah1 activity ameliorates the toxic effects of α-Syn, indicate that the diacylglycerol branch of lipid metabolism could enhance α-Syn neuronal cytotoxicity, and suggest a link between α-Syn toxicity and the biology of lipid droplets.
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Affiliation(s)
- Martin Soste
- Institute of Biochemistry, Department of Biology, ETH Zurich, Zurich, Switzerland; Institute of Molecular Systems Biology, Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Konstantina Charmpi
- CECAD, University of Cologne, Cologne, Germany; Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | - Fabienne Lampert
- Institute of Biochemistry, Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Juan Atilio Gerez
- Laboratory of Physical Chemistry, Department of Chemistry and Applied Biosciences, ETH Zurich, Zurich, Switzerland
| | - Marc van Oostrum
- Institute of Biochemistry, Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Liliana Malinovska
- Institute of Biochemistry, Department of Biology, ETH Zurich, Zurich, Switzerland; Institute of Molecular Systems Biology, Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Paul Jonathan Boersema
- Institute of Biochemistry, Department of Biology, ETH Zurich, Zurich, Switzerland; Institute of Molecular Systems Biology, Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Natalia Cecilia Prymaczok
- Laboratory of Physical Chemistry, Department of Chemistry and Applied Biosciences, ETH Zurich, Zurich, Switzerland
| | - Roland Riek
- Laboratory of Physical Chemistry, Department of Chemistry and Applied Biosciences, ETH Zurich, Zurich, Switzerland
| | - Matthias Peter
- Institute of Biochemistry, Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Stefano Vanni
- Department of Biology, University of Fribourg, Fribourg, Switzerland
| | - Andreas Beyer
- CECAD, University of Cologne, Cologne, Germany; Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany.
| | - Paola Picotti
- Institute of Biochemistry, Department of Biology, ETH Zurich, Zurich, Switzerland; Institute of Molecular Systems Biology, Department of Biology, ETH Zurich, Zurich, Switzerland.
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38
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Haselgrübler R, Lanzerstorfer P, Röhrl C, Stübl F, Schurr J, Schwarzinger B, Schwarzinger C, Brameshuber M, Wieser S, Winkler SM, Weghuber J. Hypolipidemic effects of herbal extracts by reduction of adipocyte differentiation, intracellular neutral lipid content, lipolysis, fatty acid exchange and lipid droplet motility. Sci Rep 2019; 9:10492. [PMID: 31324860 PMCID: PMC6642187 DOI: 10.1038/s41598-019-47060-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Accepted: 07/05/2019] [Indexed: 12/12/2022] Open
Abstract
An increase in adipose tissue is caused by the increased size and number of adipocytes. Lipids accumulate in intracellular stores, known as lipid droplets (LDs). Recent studies suggest that parameters such as LD size, shape and dynamics are closely related to the development of obesity. Berberine (BBR), a natural plant alkaloid, has been demonstrated to possess anti-obesity effects. However, it remains unknown which cellular processes are affected by this compound or how effective herbal extracts containing BBR and other alkaloids actually are. For this study, we used extracts of Coptis chinensis, Mahonia aquifolium, Berberis vulgaris and Chelidonium majus containing BBR and other alkaloids and studied various processes related to adipocyte functionality. The presence of extracts resulted in reduced adipocyte differentiation, as well as neutral lipid content and rate of lipolysis. We observed that the intracellular fatty acid exchange was reduced in different LD size fractions upon treatment with BBR and Coptis chinensis. In addition, LD motility was decreased upon incubation with BBR, Coptis chinensis and Chelidonium majus extracts. Furthermore, Chelidonium majus was identified as a potent fatty acid uptake inhibitor. This is the first study that demonstrates the selected regulatory effects of herbal extracts on adipocyte function.
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Affiliation(s)
| | | | - Clemens Röhrl
- University of Applied Sciences Upper Austria, Wels, Austria.,Institute of Medical Chemistry, Center for Pathobiochemistry and Genetics, Medical University of Vienna, Vienna, Austria
| | - Flora Stübl
- University of Applied Sciences Upper Austria, Wels, Austria
| | - Jonas Schurr
- University of Applied Sciences Upper Austria, Hagenberg, Austria
| | - Bettina Schwarzinger
- Austrian Competence Center for Feed and Food Quality, Safety and Innovation, Wels, Austria
| | - Clemens Schwarzinger
- Johannes Kepler University, Institute for Chemical Technology of Organic Materials, Linz, Austria
| | | | - Stefan Wieser
- ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, 08860 Castelldefels, Barcelona, Spain
| | | | - Julian Weghuber
- University of Applied Sciences Upper Austria, Wels, Austria. .,Austrian Competence Center for Feed and Food Quality, Safety and Innovation, Wels, Austria.
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39
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Gu Y, Yang Y, Cao X, Zhao Y, Gao X, Sun C, Zhang F, Yuan Y, Xu Y, Zhang J, Xiao L, Ye J. Plin3 protects against alcoholic liver injury by facilitating lipid export from the endoplasmic reticulum. J Cell Biochem 2019; 120:16075-16087. [PMID: 31119787 DOI: 10.1002/jcb.28889] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Revised: 03/01/2019] [Accepted: 03/15/2019] [Indexed: 12/20/2022]
Abstract
Hepatic lipid accumulation is the most common pathological characteristic of alcoholic liver disease (ALD). In mammalian cells, excess neutral lipids are stored in lipid droplets (LDs). As a member of perilipin family proteins, Plin3 was recently found to regulate the LD biogenesis. However, the roles and mechanism of Plin3 in ALD progression remain unclear. Herein, we found that alcohol stimulated Plin3 expression in both mouse livers and cultured AML12 mouse hepatic cells, which was accompanied by excess LD accumulation in hepatocytes. The elevations of Plin3 in alcohol-treated hepatocytes paralleled with the levels of both PPARα and γ, and the protein degradation of Plin3 was also reduced after alcohol exposure. Moreover, Plin3 knockdown increased cellular sensitivity to alcohol-induced apoptosis, endoplasmic reticulum (ER) stress, and inflammatory cytokines release, including TNF-α, IL-1, and IL-6β. Notably, alcohol exacerbated triglycerides (TG) accumulation in the ER and caused ER dilation in Plin3-knockdown AML12 cells. Finally, we observed that Plin3 interacted with dynein subunit Dync1i1 and mediated the colocalization of LDs and microtubules, while high concentration of alcohol disrupted microtubules and caused dispersion of excess small LDs in cytoplasm. Summarily, Plin3 promotes lipid export from the ER and reduces ER lipotoxic stress, thereby, protecting against alcoholic liver injury. Moreover, Plin3 could be an adapter protein mediating LD transport by microtubules. This study explored the roles of Plin3 in alcohol-induced hepatic injury, suggesting Plin3 as a potential target for the prevention of ALD progression.
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Affiliation(s)
- Yu Gu
- State Key Laboratory of Cancer Biology and Department of Pathology, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, China.,Department of Pathology, Basic Medicine School, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Ying Yang
- Department of Pathology, Basic Medicine School, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Xiangmei Cao
- Department of Pathology, Basic Medical School, Ningxia Medical University, Yinchuan, Ningxia, China
| | - Yuanlin Zhao
- State Key Laboratory of Cancer Biology and Department of Pathology, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Xing Gao
- State Key Laboratory of Cancer Biology and Department of Pathology, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Chao Sun
- State Key Laboratory of Cancer Biology and Department of Pathology, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, China.,Department of Neurology, Tangdu Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Feng Zhang
- State Key Laboratory of Cancer Biology and Department of Pathology, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, China.,Department of Pathology, Basic Medicine School, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Yuan Yuan
- Department of Pathology, Basic Medicine School, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Yuqiao Xu
- State Key Laboratory of Cancer Biology and Department of Pathology, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, China.,Department of Pathology, Basic Medicine School, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Jin Zhang
- Department of Pathology, Basic Medicine School, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Liming Xiao
- State Key Laboratory of Cancer Biology and Department of Pathology, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Jing Ye
- State Key Laboratory of Cancer Biology and Department of Pathology, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, China.,Department of Pathology, Basic Medicine School, The Fourth Military Medical University, Xi'an, Shaanxi, China
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40
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Jackson CL. Lipid droplet biogenesis. Curr Opin Cell Biol 2019; 59:88-96. [PMID: 31075519 DOI: 10.1016/j.ceb.2019.03.018] [Citation(s) in RCA: 73] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 03/24/2019] [Accepted: 03/29/2019] [Indexed: 11/18/2022]
Abstract
Lipid droplets (LDs) store neutral lipids in their core as an energy source when nutrients are scarce. The center of an LD is hydrophobic, and hence it is surrounded by a phospholipid monolayer, unlike other organelles that have an aqueous interior and are bounded by a phospholipid bilayer. LDs arise from the ER, where neutral lipid synthesis enzymes are localized. A combination of biophysical analysis and modeling, in vitro reconstitution and cell biological analyses has provided a great deal of information over the past few years on the process of LD biogenesis from the ER. In addition to lipid composition, four protein families (seipin proteins, perilipins, FIT proteins and ER shaping proteins) are crucial for LD biogenesis. Recent studies have shown that LDs preferentially arise, along with peroxisomes, at special ER sites marked by the reticulon-like Pex30/MCTP2 protein. New functions for perilipins and FIT family proteins have been uncovered, and the cryo-electron microscopy structure of seipin coupled with high resolution imaging in cells has provided a more comprehensive picture of its function in LD biogenesis. Seipin, along with other proteins such as Rab18 and its effector NRZ, have been shown to carry out their functions at least in part through regulation of ER-LD contact sites, whose establishment and maintenance have emerged as an essential component of LD biogenesis and maturation.
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Affiliation(s)
- Catherine L Jackson
- Institut Jacques Monod, UMR7592 CNRS Université Paris-Diderot, Sorbonne Paris Cité, Paris, France.
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41
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Nettebrock NT, Bohnert M. Born this way - Biogenesis of lipid droplets from specialized ER subdomains. Biochim Biophys Acta Mol Cell Biol Lipids 2019; 1865:158448. [PMID: 31028912 DOI: 10.1016/j.bbalip.2019.04.008] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 12/20/2018] [Accepted: 01/06/2019] [Indexed: 01/21/2023]
Abstract
Both the endoplasmic reticulum (ER) and lipid droplets (LDs) are key players in lipid handling. In addition to this functional connection, the two organelles are also tightly linked due to the fact that the ER is the birthplace of LDs. LDs have an atypical architecture, consisting of a neutral lipid core that is covered by a phospholipid monolayer. LD biogenesis starts with neutral lipid synthesis in the ER membrane and formation of small neutral lipid lenses between its leaflets, followed by budding of mature LDs toward the cytosol. Several ER proteins have been identified that are required for efficient LD formation, among them seipin, Pex30, and FIT2. Recent evidence indicates that these LD biogenesis factors might cooperate with specific lipids, thus generating ER subdomains optimized for LD assembly. Intriguingly, LD biogenesis reacts dynamically to nutrient stress, resulting in a spatial reorganization of LD formation in the ER.
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Affiliation(s)
- Niclas T Nettebrock
- Institute of Cell Dynamics and Imaging, University of Münster, Von-Esmarch-Str. 56, 48149 Münster, Germany; Cells-in-Motion Cluster of Excellence (EXC 1003 - CiM), University of Münster, Germany
| | - Maria Bohnert
- Institute of Cell Dynamics and Imaging, University of Münster, Von-Esmarch-Str. 56, 48149 Münster, Germany; Cells-in-Motion Cluster of Excellence (EXC 1003 - CiM), University of Münster, Germany.
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42
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Abstract
Lipid droplets are storage organelles at the centre of lipid and energy homeostasis. They have a unique architecture consisting of a hydrophobic core of neutral lipids, which is enclosed by a phospholipid monolayer that is decorated by a specific set of proteins. Originating from the endoplasmic reticulum, lipid droplets can associate with most other cellular organelles through membrane contact sites. It is becoming apparent that these contacts between lipid droplets and other organelles are highly dynamic and coupled to the cycles of lipid droplet expansion and shrinkage. Importantly, lipid droplet biogenesis and degradation, as well as their interactions with other organelles, are tightly coupled to cellular metabolism and are critical to buffer the levels of toxic lipid species. Thus, lipid droplets facilitate the coordination and communication between different organelles and act as vital hubs of cellular metabolism.
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Affiliation(s)
- James A Olzmann
- Department of Nutritional Sciences and Toxicology, University of California-Berkeley, Berkeley, CA, USA.
| | - Pedro Carvalho
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK.
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43
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Ajjaji D, Ben M'barek K, Mimmack ML, England C, Herscovitz H, Dong L, Kay RG, Patel S, Saudek V, Small DM, Savage DB, Thiam AR. Dual binding motifs underpin the hierarchical association of perilipins1-3 with lipid droplets. Mol Biol Cell 2019; 30:703-716. [PMID: 30649995 PMCID: PMC6589688 DOI: 10.1091/mbc.e18-08-0534] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 01/07/2019] [Accepted: 01/08/2019] [Indexed: 01/03/2023] Open
Abstract
Lipid droplets (LDs) in all eukaryotic cells are coated with at least one of the perilipin (Plin) family of proteins. They all regulate key intracellular lipases but do so to significantly different extents. Where more than one Plin is expressed in a cell, they associate with LDs in a hierarchical manner. In vivo, this means that lipid flux control in a particular cell or tissue type is heavily influenced by the specific Plins present on its LDs. Despite their early discovery, exactly how Plins target LDs and why they displace each other in a "hierarchical" manner remains unclear. They all share an amino-terminal 11-mer repeat (11mr) amphipathic region suggested to be involved in LD targeting. Here, we show that, in vivo, this domain functions as a primary highly reversible LD targeting motif in Plin1-3, and, in vitro, we document reversible and competitive binding between a wild-type purified Plin1 11mr peptide and a mutant with reduced binding affinity to both "naked" and phospholipid-coated oil-water interfaces. We also present data suggesting that a second carboxy-terminal 4-helix bundle domain stabilizes LD binding in Plin1 more effectively than in Plin2, whereas it weakens binding in Plin3. These findings suggest that dual amphipathic helical regions mediate LD targeting and underpin the hierarchical binding of Plin1-3 to LDs.
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Affiliation(s)
- Dalila Ajjaji
- Laboratoire de Physique de l’Ecole Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université Paris-Diderot, Sorbonne Paris Cité, Paris, France
| | - Kalthoum Ben M'barek
- Laboratoire de Physique de l’Ecole Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université Paris-Diderot, Sorbonne Paris Cité, Paris, France
| | - Michael L. Mimmack
- University of Cambridge Metabolic Research Laboratories, Wellcome Trust-Medical Research Council Institute of Metabolic Science, Cambridge CB2 0QQ, United Kingdom
| | - Cheryl England
- Department of Physiology & Biophysics, Boston University School of Medicine, Boston, MA 02118
| | - Haya Herscovitz
- Department of Physiology & Biophysics, Boston University School of Medicine, Boston, MA 02118
| | - Liang Dong
- University of Cambridge Metabolic Research Laboratories, Wellcome Trust-Medical Research Council Institute of Metabolic Science, Cambridge CB2 0QQ, United Kingdom
| | - Richard G. Kay
- University of Cambridge Metabolic Research Laboratories, Wellcome Trust-Medical Research Council Institute of Metabolic Science, Cambridge CB2 0QQ, United Kingdom
| | - Satish Patel
- University of Cambridge Metabolic Research Laboratories, Wellcome Trust-Medical Research Council Institute of Metabolic Science, Cambridge CB2 0QQ, United Kingdom
| | - Vladimir Saudek
- University of Cambridge Metabolic Research Laboratories, Wellcome Trust-Medical Research Council Institute of Metabolic Science, Cambridge CB2 0QQ, United Kingdom
| | - Donald M. Small
- Department of Physiology & Biophysics, Boston University School of Medicine, Boston, MA 02118
| | - David B. Savage
- University of Cambridge Metabolic Research Laboratories, Wellcome Trust-Medical Research Council Institute of Metabolic Science, Cambridge CB2 0QQ, United Kingdom
| | - Abdou Rachid Thiam
- Laboratoire de Physique de l’Ecole Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université Paris-Diderot, Sorbonne Paris Cité, Paris, France
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44
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Shew T, Wolins NE, Cifarelli V. VEGFR-3 Signaling Regulates Triglyceride Retention and Absorption in the Intestine. Front Physiol 2018; 9:1783. [PMID: 30618798 PMCID: PMC6297147 DOI: 10.3389/fphys.2018.01783] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Accepted: 11/26/2018] [Indexed: 12/22/2022] Open
Abstract
The lymphatic system transports dietary lipids absorbed and packaged as chylomicrons by enterocytes, for delivery to the bloodstream. Once considered a passive drainage, chylomicron entry into intestinal lymphatic vessels, or lacteals, is now emerging to be an active process controlled by a dynamic and complex regulation. Vascular endothelial growth factor (VEGF)-C, a major lymphangiogenic factor, regulates lacteal maintenance and function. Little is known about the role of its cognate tyrosine kinase VEGF receptor 3 (VEGFR-3) during lipid absorption. Here we investigated role of VEGFR-3 signaling in triglyceride (TG) absorption and distribution into tissues using the Chy mouse model, which bears an inactivating mutation in the tyrosine kinase domain of VEGFR-3 (heterozygous A3157T mutation resulting in I1053F substitution). Our data show that inactivation of VEGFR-3 tyrosine kinase motif leads to retention of TGs in the enterocytes of the small intestine, decreased postprandial levels of TGs in the plasma and increased excretion of free fatty acids (FFAs) and TGs into their stools. We further show that levels of nitric oxide (NO), required for chylomicron mobilization into the bloodstream, are significantly reduced in the Chy intestine after a fat bolus suggesting a critical role for VEGFR-3 signaling in the generation of NO during lipid absorption. Our data support the hypothesis that VEGFR-3 signaling plays an important role in chylomicron-TG entry into lacteals, possibly affecting TG trafficking to peripheral tissues.
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Affiliation(s)
- Trevor Shew
- Department of Medicine, Center for Human Nutrition, Washington University School of Medicine, St. Louis, MO, United States
| | - Nathan E Wolins
- Department of Medicine, Center for Human Nutrition, Washington University School of Medicine, St. Louis, MO, United States
| | - Vincenza Cifarelli
- Department of Medicine, Center for Human Nutrition, Washington University School of Medicine, St. Louis, MO, United States
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45
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Salo VT, Ikonen E. Moving out but keeping in touch: contacts between endoplasmic reticulum and lipid droplets. Curr Opin Cell Biol 2018; 57:64-70. [PMID: 30476754 DOI: 10.1016/j.ceb.2018.11.002] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Revised: 11/06/2018] [Accepted: 11/07/2018] [Indexed: 12/14/2022]
Abstract
The formation of neutral lipid filled and phospholipid monolayer engulfed lipid droplets (LDs) from the bilayer of the endoplasmic reticulum (ER) is an active area of investigation. This process harnesses the biophysical properties of the lipids involved and necessitates cooperation of protein machineries in both organelle membranes. Increasing evidence suggests that once formed, LDs keep close contact to the mother organelle and that this may be achieved via several, morphologically distinct and potentially functionally specialized connections. These may help LDs to dynamically respond to changes in lipid metabolic status sensed by the ER. In this review, we will discuss recent progress in understanding how LDs interact with the ER.
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Affiliation(s)
- Veijo T Salo
- Faculty of Medicine, Dept. of Anatomy and HiLIFE, Univ. of Helsinki, Finland; Minerva Foundation Institute for Medical Research, Helsinki, Finland
| | - Elina Ikonen
- Faculty of Medicine, Dept. of Anatomy and HiLIFE, Univ. of Helsinki, Finland; Minerva Foundation Institute for Medical Research, Helsinki, Finland
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Gemmink A, Daemen S, Kuijpers HJH, Schaart G, Duimel H, López-Iglesias C, van Zandvoort MAMJ, Knoops K, Hesselink MKC. Super-resolution microscopy localizes perilipin 5 at lipid droplet-mitochondria interaction sites and at lipid droplets juxtaposing to perilipin 2. Biochim Biophys Acta Mol Cell Biol Lipids 2018; 1863:1423-1432. [PMID: 30591149 DOI: 10.1016/j.bbalip.2018.08.016] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Revised: 08/06/2018] [Accepted: 08/29/2018] [Indexed: 01/26/2023]
Abstract
OBJECTIVE Intramyocellular lipid droplets (LD) and their coat proteins PLIN2 and PLIN5 are involved in lipolysis, with a putative role for PLIN5 in mitochondrial tethering. Reportedly, these proteins co-localize and cover the surface of the LD. To provide the spatial basis for understanding how these proteins possess their distinct roles, we examined the precise location of PLIN2 and PLIN5 and explored PLIN5 presence at LD-mitochondria contact sites using Stimulated emission depletion (STED) microscopy and correlative light-electron microscopy (CLEM) in human skeletal muscle sections. METHODS LDs were stained by MDH together with combinations of mitochondrial proteins and PLINs. Subcellular distribution and co-localization of PLIN proteins and mitochondria was imaged by STED microscopy (Leica TCS SP8) and quantified using Pearson's correlation coefficients and intensity profile plots. CLEM was employed to examine the presence of PLIN5 on mitochondria-LD contact sites. RESULTS Both PLIN2 and PLIN5 localized to the LD in a dot-like, juxtaposed fashion rather than colocalizing and covering the entire LD. Both STED and CLEM revealed a high fraction of PLIN5 at the LD-mitochondria interface, but not at mitochondrial cristae, as suggested previously. CONCLUSION Using two super-resolution imaging approaches, this is the first study to show that in sections of human skeletal muscle PLIN2 and PLIN5 localize to the LD at distinct sites, with abundance of PLIN5 at LD-mitochondria tethering sites. This novel spatial information uncovers that PLIN proteins do not serve as lipolytic barriers but rather are docking sites for proteins facilitating selective lipase access under a variety of lipolytic conditions.
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Affiliation(s)
- Anne Gemmink
- Department of Nutrition and Movement Sciences, Maastricht University Medical Centre+, 6200 MD Maastricht, the Netherlands; NUTRIM School for Nutrition and Translational Research in Metabolism, Maastricht, the Netherlands
| | - Sabine Daemen
- Department of Nutrition and Movement Sciences, Maastricht University Medical Centre+, 6200 MD Maastricht, the Netherlands; NUTRIM School for Nutrition and Translational Research in Metabolism, Maastricht, the Netherlands
| | - Helma J H Kuijpers
- Microscopy Core Lab, FHML and M4I Maastricht Multimodal Molecular Imaging Institute, Maastricht University, 6200 MD Maastricht, the Netherlands
| | - Gert Schaart
- Department of Nutrition and Movement Sciences, Maastricht University Medical Centre+, 6200 MD Maastricht, the Netherlands; NUTRIM School for Nutrition and Translational Research in Metabolism, Maastricht, the Netherlands
| | - Hans Duimel
- Microscopy Core Lab, FHML and M4I Maastricht Multimodal Molecular Imaging Institute, Maastricht University, 6200 MD Maastricht, the Netherlands
| | - Carmen López-Iglesias
- Microscopy Core Lab, FHML and M4I Maastricht Multimodal Molecular Imaging Institute, Maastricht University, 6200 MD Maastricht, the Netherlands
| | - Marc A M J van Zandvoort
- Department of Genetics & Cell Biology - Molecular Cell Biology, Maastricht University Medical Centre+, 6200 MD Maastricht, the Netherlands; CARIM - Cardiovascular Research Institute Maastricht, Maastricht, the Netherlands; Institute for Molecular Cardiovascular Research IMCAR, Universitätsklinikum, Aachen, Pauwelstrasse 30, Aachen, Germany
| | - Kèvin Knoops
- Microscopy Core Lab, FHML and M4I Maastricht Multimodal Molecular Imaging Institute, Maastricht University, 6200 MD Maastricht, the Netherlands
| | - Matthijs K C Hesselink
- Department of Nutrition and Movement Sciences, Maastricht University Medical Centre+, 6200 MD Maastricht, the Netherlands; NUTRIM School for Nutrition and Translational Research in Metabolism, Maastricht, the Netherlands.
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Martins AS, Martins IC, Santos NC. Methods for Lipid Droplet Biophysical Characterization in Flaviviridae Infections. Front Microbiol 2018; 9:1951. [PMID: 30186265 PMCID: PMC6110928 DOI: 10.3389/fmicb.2018.01951] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Accepted: 08/02/2018] [Indexed: 01/14/2023] Open
Abstract
Lipid droplets (LDs) are intracellular organelles for neutral lipid storage, originated from the endoplasmic reticulum. They play an essential role in lipid metabolism and cellular homeostasis. In fact, LDs are complex organelles, involved in many more cellular processes than those initially proposed. They have been extensively studied in the context of LD-associated pathologies. In particular, LDs have emerged as critical for virus replication and assembly. Viruses from the Flaviviridae family, namely dengue virus (DENV), hepatitis C virus (HCV), West Nile virus (WNV), and Zika virus (ZIKV), interact with LDs to usurp the host lipid metabolism for their own viral replication and pathogenesis. In general, during Flaviviridae infections it is observed an increasing number of host intracellular LDs. Several viral proteins interact with LDs during different steps of the viral life cycle. The HCV core protein and DENV capsid protein, extensively interact with LDs to regulate their replication and assembly. Detailed studies of LDs in viral infections may contribute for the development of possible inhibitors of key steps of viral replication. Here, we reviewed different techniques that can be used to characterize LDs isolated from infected or non-infected cells. Microscopy studies have been commonly used to observe LDs accumulation and localization in infected cell cultures. Fluorescent dyes, which may affect LDs directly, are widely used to probe LDs but there are also approaches that do not require the use of fluorescence, namely stimulated Raman scattering, electron and atomic force microscopy-based approaches. These three are powerful techniques to characterize LDs morphology. Raman scattering microscopy allows studying LDs in a single cell. Electron and atomic force microscopies enable a better characterization of LDs in terms of structure and interaction with other organelles. Other biophysical techniques, such as dynamic light scattering and zeta potential are also excellent to characterize LDs in terms of size in a simple and fast way and test possible LDs interaction with viral proteins. These methodologies are reviewed in detail, in the context of viral studies.
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Affiliation(s)
- Ana S Martins
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal
| | - Ivo C Martins
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal
| | - Nuno C Santos
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal
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Henne WM, Reese ML, Goodman JM. The assembly of lipid droplets and their roles in challenged cells. EMBO J 2018; 37:embj.201898947. [PMID: 29789390 DOI: 10.15252/embj.201898947] [Citation(s) in RCA: 169] [Impact Index Per Article: 28.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Revised: 03/08/2018] [Accepted: 03/22/2018] [Indexed: 12/14/2022] Open
Abstract
Cytoplasmic lipid droplets are important organelles in nearly every eukaryotic and some prokaryotic cells. Storing and providing energy is their main function, but they do not work in isolation. They respond to stimuli initiated either on the cell surface or in the cytoplasm as conditions change. Cellular stresses such as starvation and invasion are internal insults that evoke changes in droplet metabolism and dynamics. This review will first outline lipid droplet assembly and then discuss how droplets respond to stress and in particular nutrient starvation. Finally, the role of droplets in viral and microbial invasion will be presented, where an unresolved issue is whether changes in droplet abundance promote the invader, defend the host, to try to do both. The challenges of stress and infection are often accompanied by changes in physical contacts between droplets and other organelles. How these changes may result in improving cellular physiology, an ongoing focus in the field, is discussed.
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Affiliation(s)
- W Mike Henne
- Department of Cell Biology, University of Texas Southwestern Medical School, Dallas, TX, USA
| | - Michael L Reese
- Department of Pharmacology, University of Texas Southwestern Medical School, Dallas, TX, USA
| | - Joel M Goodman
- Department of Pharmacology, University of Texas Southwestern Medical School, Dallas, TX, USA
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Xu S, Zhang X, Liu P. Lipid droplet proteins and metabolic diseases. Biochim Biophys Acta Mol Basis Dis 2018; 1864:1968-1983. [DOI: 10.1016/j.bbadis.2017.07.019] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Revised: 07/14/2017] [Accepted: 07/19/2017] [Indexed: 12/13/2022]
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50
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Čopič A, Antoine-Bally S, Giménez-Andrés M, La Torre Garay C, Antonny B, Manni MM, Pagnotta S, Guihot J, Jackson CL. A giant amphipathic helix from a perilipin that is adapted for coating lipid droplets. Nat Commun 2018; 9:1332. [PMID: 29626194 PMCID: PMC5889406 DOI: 10.1038/s41467-018-03717-8] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Accepted: 03/05/2018] [Indexed: 11/21/2022] Open
Abstract
How proteins are targeted to lipid droplets (LDs) and distinguish the LD surface from the surfaces of other organelles is poorly understood, but many contain predicted amphipathic helices (AHs) that are involved in targeting. We have focused on human perilipin 4 (Plin4), which contains an AH that is exceptional in terms of length and repetitiveness. Using model cellular systems, we show that AH length, hydrophobicity, and charge are important for AH targeting to LDs and that these properties can compensate for one another, albeit at a loss of targeting specificity. Using synthetic lipids, we show that purified Plin4 AH binds poorly to lipid bilayers but strongly interacts with pure triglycerides, acting as a coat and forming small oil droplets. Because Plin4 overexpression alleviates LD instability under conditions where their coverage by phospholipids is limiting, we propose that the Plin4 AH replaces the LD lipid monolayer, for example during LD growth. Lipid droplets are cellular organelles important for cellular homeostasis and their disruption has been implicated in many diseases. Here the authors use a large amphipathic helix from perilipin 4 to uncover parameters important for specific lipid droplet targeting and stabilization of the oil core.
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Affiliation(s)
- Alenka Čopič
- Institut Jacques Monod, CNRS, UMR 7592, Université Paris Diderot, Sorbonne Paris Cité, 75013, Paris, France.
| | - Sandra Antoine-Bally
- Institut Jacques Monod, CNRS, UMR 7592, Université Paris Diderot, Sorbonne Paris Cité, 75013, Paris, France
| | - Manuel Giménez-Andrés
- Institut Jacques Monod, CNRS, UMR 7592, Université Paris Diderot, Sorbonne Paris Cité, 75013, Paris, France.,Université Paris-Sud, Université Paris-Saclay, 91405, Orsay, France
| | - César La Torre Garay
- Institut Jacques Monod, CNRS, UMR 7592, Université Paris Diderot, Sorbonne Paris Cité, 75013, Paris, France
| | - Bruno Antonny
- Université Côte d'Azur, CNRS, IPMC, 06560, Valbonne, France
| | - Marco M Manni
- Université Côte d'Azur, CNRS, IPMC, 06560, Valbonne, France
| | | | - Jeanne Guihot
- Institut Jacques Monod, CNRS, UMR 7592, Université Paris Diderot, Sorbonne Paris Cité, 75013, Paris, France
| | - Catherine L Jackson
- Institut Jacques Monod, CNRS, UMR 7592, Université Paris Diderot, Sorbonne Paris Cité, 75013, Paris, France
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